@James Weatherhead I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this! Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others ", I'll repost your solution in case you'd like to "Accept " the answer.
Issue:unable to reset the admin password for your SQL Azure server. you are receiving an error message "Failed to overwrite server firewall rules and refresh blade
Solution: As you mentioned It turns out that Microsoft has stopped Classic Administrator from having true admin access despite the email stating that it is valid until August 2024. I had to go into the IAM blade in Azure Sql Server and add the RBAC roles "Owner" and "SQL Security Manager". Once added i opened a new browser windows in private mode, logged in and i can now reset the admin password.
If you have any other questions or are still running into more issues, please let me know. Thank you again for your time and patience throughout this issue.
Please remember to "Accept Answer" if any answer/reply helped, so that others in the community facing similar issues can easily find the solution.
Regards
Geetha