Accounting entry in software

I think in this case, commission is being received regularly throughout the month and you are raising invoice at the month end for the commission received during the month. In such case, it is to be treated as Advance Receipt of the Commission. Upon raising Invoice, at the month end, the Invoice amount gets adjusted against the Advances Received. If the understanding is correct, then Commission Received in Advance will be subject to GST.

Sir,

i.e Today morning we purchased 10000/- we buy for cash/bank. end of the day we received 500/- commission

This commission also we received as goods.

purchase ac      Dr  10000

To Bank                                10000

then we got commission as cash/bank

bank ac             Dr    500

To commission                      500

then again the commission we made purchase

purchase a/c    dr   500

to bank                             500

In the meantime end of the month we raise an invoice for the 500/- (for example) actually many purchases.

can we entry 

commission receivable   dr       500

to commission                                  500

if it is correct how to close the commission receivable sir?