HTTP Status 500 - Request processing failed; nested exception is java.lang.NullPointerException

Hello friends, Have encoutered a runtime exception while i was creating a cohort report form. Have recognised the problem may be in my tomcat but could not understand exactly where the problem may arise from. here is a pastebin link cc @mozzy, @dkayiwa

have you made any code changes any were?

No havent made any code changes

could this be help

thanks @herbert24 thats the procedure i was following in creating a cohort report but got that error logs in the above pastebin

there is something i have realised just now into the error logs of my tomcat, what could be the problem, this is tomcat logs thanks

Are you able to reproduce it on the demo server?

@dkayiwa not yet let me try reproducing it on the demo server thanks

Problem solved after using the demo server and finally when i used the RA following the exact procedures i got where i was stuck and fixed it, thanks @dkayiwa, @herbert24

Was those changes didnot make any sense
just wanted to inbox you