Hello,
Thank you for contacting Rank Math and sorry for any inconvenience that might have been caused due to that.
Please try going through the connection process again by going through the following the following:
1. You should not be using Google Analytics v4 or Matomo Analytics.
2. Update to the latest version of Rank Math Free & PRO
3. Disconnect and reconnect your account from inside WordPress:

4. You should also delete RankMath’s app from here:
https://myaccount.google.com/permissions

5. Reconnect the account inside Rank Math by clicking here and ensure you are using the correct Google account then approve all the permission notices that shows up :
WP Dashboard >> Rank Math >> General Settings >> Analytics tab, and click the Reconnect
link

Let us know if this helps you.
We really look forward to helping you.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.