Error/Bug in GSTR 3B report

I’m currently using version 12 of ErpNext and there seems to be an error in the GSTR - 3B report. The ’ Values of exempt, nil rated and non-GST inward supplies’ seem to be showing random figures. The actual values should be 0, however, the values printed in the reports are much more than the actual purchase value of the entire year. Is there a bug in the software? Or are we doing something wrong? Thanks for your time!