How to change pan in gst

Dear Sir,

We request your kind attention to the matter that, we had enrolled in GST on 27 and got registration.But the PAN number in the Provisional Registration Certificate is different from our original PAN.

Our request is,

1- What will we do for correct this mistake in PAN number?

2- Do we need for re-registration and could we get tax input credit in existing         GST number? 

We have already contacted with the Tax Dept.But they don't know the solution !