Hello! I'm Jen, and I'd be happy to help you out with this issue.
I'm sorry to hear about this issue. I'm afraid the only way to find out why your account is temporarily restricted and hopefully recover it is to contact Microsoft Rewards Support. Only the Support Team has access to your account and can determine whether or not you have actually violated any of their requirements. Thank you for your kind understanding.
https://rewards.bing.com/support
I hope this information helps. If you have any questions, please let me know and I'll be glad to assist you further.
Best Regards!
Jen :)