Invoice not filed last year gst (2017 - 2018) and payment received for the same in current year (2018 -2019)

Hello,

As my client was not giving me any payment so I did not filed that client bills in GST as we were not financial capable to pay GST for the amount which we haven't received and even we didn't knew if we will receive it or not.

But now they are releasing the payment for that bills which I raised last financial year "what to do"

So far we have not filed the Income Tax due to Audit

Please let me know if there is any solution for the same.

Thank You