Hi Khalida,
Based on your sharing, I have tried to reproduce the issue on my side but on my testing environment, the copy paste feature in Loop still works properly. I can copy and paste multiple rows from a Loop table or from another source like Excel into a Loop table. I have also checked the Service Health Status in Microsoft 365 Admin Center but as of now, there is no incident or service degradation happening that related to Microsoft Loop and also no official documentation or issue announcement addressing this behavior.
However, it's a high possibility that there could be an ongoing issue with the copy paste feature with Loop since I have found a post that reported the same issue as you're experiencing just a few days ago. That user also reported that the issue happened with all Loop tables and it still persisted even when she tried with a fresh new table. You can find more details about her sharing in this post to see if you also have the same experiment: Microsoft Teams Loop Component pasting issues - Microsoft Q&A
I'm truly sorry that I couldn't gather any further details or insights into the root cause or a permanent solution for this issue. That said, for you to receive the best possible solution, I suggest you should contact your IT admin and ask for their help to create a service request with Microsoft support to get advanced technical assistance and diagnostics from Microsoft 365 Admin Center > Support > Help & Support. This route ensures that you can contact a Microsoft support engineer who can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, he/she can escalate it to a specialized team for deeper analysis.
As a forum moderator, I genuinely wish I could directly access your device or delve into the backend systems to diagnose and fix this for you. However, my role here is limited to providing general guidance and solutions that can be applied by users. Please know that even though I can't directly intervene, directing you to the correct, specialized support is the most effective help I can provide from my position.
Thank you for your understanding and I truly hope your issue will be get sorted out soon.
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