Thank you for posting here in the Community, @reeja. It could be that your GST isn't set up in QuickBooks that's why it's not showing in the GST report.
To set up your QuickBooks GST, you'll need to get GST registered first, then add your GSTIN details. Here's how:
GST for QuickBooks companies that have set up tax agencies
GST for QuickBooks companies without taxes setup
Companies (existing and new) that have not enabled tax will see a Setup GST widget on the dashboard page. Here's how:
Once done, follow Step 3: Add your HSN, SAC codes outlined in this help article: Setting up QuickBooks for GST.
For additional information, you can click this article: The GSTR3B (GSTR 3B) report in QuickBooks.
For future reference, check out this article to see information on how QuickBooks pulls in your transactions into the GSTR4 report: The GSTR4 report in QuickBooks.
Please know that you are always welcome to post in the Community if you have any other concerns. Wishing you and your business continued success.