Hi there,
Try running the Windows Remote Assistance as administrator.
Click Start, type Remote Assistance in the Search box, right-click on Windows Remote Assistance and choose Run as administrator.
If this doesn't help you then Open Local Group Policy Editor via the command gpedit.msc on the PC which you offer remote assistance. Navigate to Computer Configuration \ Administrative Templates \ System \ Remote Assistance.
-Double click Solicited Remote Assistance and choose the Enable option, choose to Allow helps to remotely control the computer.
Here is a thread as well that discusses the same issue and you can try out some troubleshooting steps from this and see if that helps you to sort the Issue.
Your offer to help could not be sent
https://social.technet.microsoft.com/Forums/windows/en-US/6bd692b0-b833-48e5-a125-5bebede91cef/your-offer-to-help-could-not-be-sent?forum=w7itpronetworking
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