You can give a try for correction of form by contacting National Testing Agency through following email :-

 Ntanationaltestingagency@gmail.com

You can ask your doubt about board roll number mistake via mail by mentioning following details : name of candidate,  registration ID/Applicayion number and mistakes made in the application form.

You would then get the solution through their reply. 

All the best.  

hello,

i think this won't be considered as issue.but you can try by mailing jee main authorities.you may get any help by refering the official website for correcting application form.dont worry, it won't be the issue.

the candidates should correctly enter their date of birth,name and mark details.so roll number wont make any issue.

thank you!