Hello Sushmita,

DU forms have an offering for the filling of preference for the college a candidate aspires for and when the process of allotment begins the Authority tries the level best to make each candidate meets his/her preferences but as the seats are limited every one might not get the preferred college so for them authority does whatever best can be done.

You have to join the allotted college only and if not , your admission will be summoned.

Hope this helps,

All the best !