Diff between st payable & amount charged in st3 form

I want some clarification on the ST3 Excel form for Service Tax return.
(I) Service Tax Payable : what details should be given in this part?

(II) Taxable Amount Charged : what details should be given in this?

Aren't they one and the same?

We are charging service tax in invoices .

I hvve mentiond amount only in Service Tax Payable. I have mentioned nothing in ST amount charged. Shoud i need to file revised return.