Hi Rozina,
Thank you for posting your question in the Microsoft Q&A Forum. I’m sorry to hear that you’re facing the “Too Many Requests” issue. I appreciate your efforts in trying some solutions already.
If you can access your Microsoft account, please try opening Outlook or any other affected apps from there. For Outlook, you can use the following links to check if any of them help you bypass the error: https://outlook.live.com or https://login.live.com or https://www.office.com/.
There have been reports from other users experiencing the same issue who were able to resolve it by reloading the page multiple times. While I understand this can be frustrating, you might consider trying this as a last resort, as it has worked for many people.
If your issue persists or you need further assistance, please click “Add comment” to let me know. I’ll be happy to help you resolve this problem.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.
Best regards.