diff --git a/jest.setup.js b/jest.setup.js
index 49b6721..8e9ae9a 100644
--- a/jest.setup.js
+++ b/jest.setup.js
@@ -1,4 +1,4 @@
 jest.setTimeout(1 * 1000); // 1 second
 jest.resetModules();
 jest.resetAllMocks();
-jest.useFakeTimers("modern");
\ No newline at end of file
+jest.useFakeTimers();
\ No newline at end of file
diff --git a/tests/helpers/EffectHelper.test.ts b/tests/helpers/EffectHelper.test.ts
index 21bb3e6..343f06c 100644
--- a/tests/helpers/EffectHelper.test.ts
+++ b/tests/helpers/EffectHelper.test.ts
@@ -58,7 +58,7 @@ describe("UseEffect", () => {
                 Unused: 1,
                 WhenExpires: whenExpires,
             };
-            
+
             beforeAll(async () => {
                 jest.setSystemTime(nowMock);
 
@@ -86,7 +86,7 @@ describe("UseEffect", () => {
                 UseEffect: jest.fn(),
                 Save: jest.fn(),
             };
-            
+
             beforeAll(async () => {
                 jest.setSystemTime(nowMock);
 
@@ -111,20 +111,88 @@ describe("UseEffect", () => {
         });
 
         describe("GIVEN effect.WhenExpires is null", () => {
-            test.todo("EXPECT UseEffect to be called");
+            let result: boolean | undefined;
 
-            test.todo("EXPECT effect to be saved");
+            // nowMock > whenExpires
+            const nowMock = new Date(2024, 11, 3, 13, 30);
+            const whenExpiresNew = new Date(2024, 11, 3, 15, 0);
 
-            test.todo("EXPECT true returned");
+            const userEffect = {
+                Unused: 1,
+                WhenExpires: null,
+                UseEffect: jest.fn(),
+                Save: jest.fn(),
+            };
+
+            beforeAll(async () => {
+                jest.setSystemTime(nowMock);
+
+                UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(userEffect);
+
+                result = await EffectHelper.UseEffect("userId", "name", whenExpiresNew);
+            });
+
+            test("EXPECT UseEffect to be called", () => {
+                expect(userEffect.UseEffect).toHaveBeenCalledTimes(1);
+                expect(userEffect.UseEffect).toHaveBeenCalledWith(whenExpiresNew);
+            });
+
+            test("EXPECT effect to be saved", () => {
+                expect(userEffect.Save).toHaveBeenCalledTimes(1);
+                expect(userEffect.Save).toHaveBeenCalledWith(UserEffect, userEffect);
+            });
+
+            test("EXPECT true returned", () => {
+                expect(result).toBe(true);
+            });
         });
     });
 
     describe("GIVEN effect is not in database", () => {
-        test.todo("EXPECT false returned");
+        let result: boolean | undefined;
+
+        // nowMock > whenExpires
+        const nowMock = new Date(2024, 11, 3, 13, 30);
+        const whenExpiresNew = new Date(2024, 11, 3, 15, 0);
+
+        beforeAll(async () => {
+            jest.setSystemTime(nowMock);
+
+            UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(null);
+
+            result = await EffectHelper.UseEffect("userId", "name", whenExpiresNew);
+        });
+
+        test("EXPECT false returned", () => {
+            expect(result).toBe(false);
+        });
     });
 
     describe("GIVEN effect.Unused is 0", () => {
-        test.todo("EXPECT false returned");
+        let result: boolean | undefined;
+
+        // nowMock > whenExpires
+        const nowMock = new Date(2024, 11, 3, 13, 30);
+        const whenExpiresNew = new Date(2024, 11, 3, 15, 0);
+
+        const userEffect = {
+            Unused: 0,
+            WhenExpires: null,
+            UseEffect: jest.fn(),
+            Save: jest.fn(),
+        };
+
+        beforeAll(async () => {
+            jest.setSystemTime(nowMock);
+
+            UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(userEffect);
+
+            result = await EffectHelper.UseEffect("userId", "name", whenExpiresNew);
+        });
+
+        test("EXPECT false returned", () => {
+            expect(result).toBe(false);
+        });
     });
 });
 
@@ -132,20 +200,82 @@ describe("HasEffect", () => {
     describe("GIVEN effect is in database", () => {
         describe("GIVEN effect.WhenExpires is defined", () => {
             describe("GIVEN now is before effect.WhenExpires", () => {
-                test.todo("EXPECT true returned");
+                let result: boolean | undefined;
+
+                const nowMock = new Date(2024, 11, 3, 13, 30);
+                const whenExpires = new Date(2024, 11, 3, 15, 0);
+
+                const userEffect = {
+                    WhenExpires: whenExpires,
+                };
+
+                beforeAll(async () => {
+                    jest.setSystemTime(nowMock);
+
+                    UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(userEffect);
+
+                    result = await EffectHelper.HasEffect("userId", "name");
+                });
+
+                test("EXPECT true returned", () => {
+                    expect(result).toBe(true);
+                });
             });
 
             describe("GIVEN now is after effect.WhenExpires", () => {
-                test.todo("EXPECT false returned");
+                let result: boolean | undefined;
+
+                const nowMock = new Date(2024, 11, 3, 16, 30);
+                const whenExpires = new Date(2024, 11, 3, 15, 0);
+
+                const userEffect = {
+                    WhenExpires: whenExpires,
+                };
+
+                beforeAll(async () => {
+                    jest.setSystemTime(nowMock);
+
+                    UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(userEffect);
+
+                    result = await EffectHelper.HasEffect("userId", "name");
+                });
+
+                test("EXPECT false returned", () => {
+                    expect(result).toBe(false);
+                });
             });
         });
 
         describe("GIVEN effect.WhenExpires is undefined", () => {
-            test.todo("EXPECT false returned");
+            let result: boolean | undefined;
+
+            const userEffect = {
+                WhenExpires: undefined,
+            };
+
+            beforeAll(async () => {
+                UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(userEffect);
+
+                result = await EffectHelper.HasEffect("userId", "name");
+            });
+
+            test("EXPECT false returned", () => {
+                expect(result).toBe(false);
+            });
         });
     });
 
     describe("GIVEN effect is not in database", () => {
-        test.todo("EXPECT false returned");
+        let result: boolean | undefined;
+
+        beforeAll(async () => {
+            UserEffect.FetchOneByUserIdAndName = jest.fn().mockResolvedValue(null);
+
+            result = await EffectHelper.HasEffect("userId", "name");
+        });
+
+        test("EXPECT false returned", () => {
+            expect(result).toBe(false);
+        });
     });
 });