Withdrawal my application but before they decide it

I requested to withdrawal my tier 4 application for personal reasons (I received an offer from the university I was waiting for), but yesterday I received and email saying that my visa had be issued.
I would like to know if it is possible that I have immigration problems if I receive my passport with my visa.If not how can I change to the other university? I am very worried about it.
Thank you for the assistance.

Please I need a good advice about what to do.

Just apply with a new CaS from the university. There is no need to put an explanatory letter but it might help.
No more than, have offered place at uni and want to take the place rather than go to the college.

It will have no impact on your immigration status or history.

Hi LillyMS,

Did you succeed with your application using the CAS issued by your preferred university?
I am in a similar situation. What is the latest status on the issue?
Thank you