Hello,
Thank you for contacting us and sorry for any inconvenience that might have been caused due to that.
Please try to follow the steps below and see if that works for you:
1. Make sure that you have verified your website on Google Search Console, if not, follow this guide: https://rankmath.com/kb/google-site-verification/
2. Please make sure that you are not connecting to Google Search Console via a domain property but rather a URL prefix and that you have verified the correct version of your website on the Google Search Console (HTTP or HTTPS, www or non-www).
3. Please remove RankMath’s app from your Google apps permissions: https://myaccount.google.com/permissions
4. Once done, reconnect the Google account again from WordPress Dashboard > Rank Math > General Settings > Analytics and configure the Search Console and Analytics settings again.
Kindly check all necessary checkboxes to allow Rank Math to access some of the Google Services.
If the issue persists, then we might need to take a closer look at the settings. Please edit the first post on this ticket and include your WordPress & FTP logins in the designated Sensitive Data section.
Please do take a complete backup of your website before sharing the information with us.

It is completely secure and only our support staff has access to that section. If you want, you can use the below plugin to generate a temporary login URL to your website and share that with us instead:
https://wordpress.org/plugins/temporary-login-without-password/
You can use the above plugin in conjunction with the WP Security Audit Log to monitor what changes our staff might make on your website (if any):
https://wordpress.org/plugins/wp-security-audit-log/
Let us know how it goes. Looking forward to helping you.
Thank you.