Hello,
Thank you for contacting us and sorry for any inconvenience that might have been caused due to that.
Please make sure you’ve connected correct Google account and try re-connecting your Google account with Rank Math by following the steps below:
1. Remove Rank Math’s access from Google
Please remove RankMath’s app from your Google apps permissions:
https://myaccount.google.com/permissions

2. Re-connect Google Account
After that, reconnect the Google account again by going to WordPress Dashboard > Rank Math > General Settings > Analytics and configure the Search Console and Analytics settings again properly:

3. Grant all necessary permissions
Kindly check all necessary checkboxes to allow Rank Math to access some of the Google Services. Please check my screenshot below for reference:

If the settings are not getting saved properly, please try saving the settings for the Analytics with a different browser such as Google Chrome. If you still face some issues with Chrome, then you can try it in Incognito mode just to save the settings.
Let us know how that goes. Looking 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.