Hello ,

As your query is that you have mistakenly filled the form of DU LLB where you have put your Mother's Name in the column of your Father's Name and you are worried about that. Look first of all this is not something you need to panic about, there is very simple solution go to the counselling process and let them know that you have made this thing mistakenly and provide the details of yours to them as per their need, they might need your Aadhar card or any other detail mentioning your father's and mother's name together in both and thereafter checking over and reviewing your certificate or document they will definitely change it. So first of all communicate with them during counselling process or at the time of interaction with them and let them know that this is your issue and please do rectify this because it might be an hurdle for you in the future. 

I hope your query is solved.

Thank you.