Hey there!
Nice to meet you! I'm Darhyl, an Independent Advisor. I'm sorry you are experiencing this on Microsoft Rewards.
Just a gentle reminder that we are only Microsoft users like you here in the community. We are not Microsoft employees and we do not have tools to access any Microsoft System.
Based on your description and since you have exhausted all the possible workarounds to no avail, I highly recommend you submit a ticket to Microsoft Rewards Support for further assistance as they have the tools and resources to properly investigate this case. You may contact them using the link below:
https://rewards.bing.com/support
Thank you for your kindness and understanding! Please let me know if you require further assistance.
Best regards,
Darhyl