Hey Ram.

As per the rules of CLAT once you have submitted the fees and finally submitted the form no changes can be made including any change related to your preference of Centres. So as of now you won't be able to change your centres preference, if you've submitted the form. But in the past years CLAT has opened a correction window which may/ may not be opened this year. If it is opened this year, then you can edit your preferences there. But no such official notification regarding the same is here so as of now there are less chances of the change. You can use the link below for details.

https://clatconsortiumofnlu.ac.in/instructions.html

Best of luck