Cst/vat

Sir,

pls. tell me

We are based in Goa. We have sold some material to one party  (From Mumbai) but we have delivered material in Goa itself on Form 'C'. But billing is done on Mumbai Branch.

My question is this ok.

Secondly we have paid cst @ 2% to the C.Govt.  But till date party has not given us Form 'C'

If we are not receiveing Form 'C' then what percent tax we will have to pay to the Local Govt. i.e 10.5% or 12.5% because we have already paid 2% CST.

Kindly guide.

Thanks

Urgent