What does this error message mean in Pomodoro Clock

Hi Freecodecampers,

I pass 23/29 test on Pomodoro, functionally I think my issue is that after my session timer hits 00:00 , I have to clear the setInterval before I run the break timer, but this causes a time lage and fails the tests.

This is the error message I receive,

  1. When a session countdown reaches zero (NOTE: timer MUST reach 00:00), and a new countdown begins, the element with the id of “timer-label” should display a string indicating a break has begun.
    Cannot read property ‘1’ of null
    TypeError: Cannot read property ‘1’ of null
    at l (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:657:172521)
    at a. (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:657:182983)
    at l (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:657:104661)
    at Generator._invoke (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:657:104414)
    at Generator.forEach.e. [as next] (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:657:105018)
    at r (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:1:1054)
    at i (https://cdn.freecodecamp.org/testable-projects-fcc/v1/bundle.js:1:1265)

similar error for other test failures ,

if you want to test the code yourself here is the codepen,