Course 5 Assignment 2 Trigger Word Detection

Sorry, your submission was incorrect. Please try again. Invalid control character at: line 1254 column 428470 (char 12828650)

I am passing all the test cases in the notebook but the grader is giving the above output. I have restarted the kernel and tried submitting again but the same result. What should be done to resolve this?

It is resolved now. I clicked the “restart and clear all outputs” option and then submitted and the grader passed me this time. Other than that I did not modify anything else in the notebook.