The issue is that when you increment your Session Length value, the time value of the Session shown in the clock should also update. In addition, if the timer is running, the user should not be allowed to update the session/break lengths.
Check the functionality of the example Pomodoro timer (linked to from the project’s noted Objective) and note the following about its functionality:
When you increment the session time, the timer updates
If the timer is currently running, you cannot adjust the Break or Session Length values
I was able to modify your handleSetTimers method to handle those two pieces of functionality noted above to get your version to pass all tests. Spend some time in that method thinking about how to implement those.