TeamViewer is frozen on remote

I had 2 cases in one week where the remote device (iMac) runs normally but TeamViewer is not visible remotely.

In the first time I had a tech visit the facility and reboot the iMac and this solved the problem.  Today the problem recurred.

Is there a way to startle the Teamviewer to wakeup or to reboot the remote iMac?  I am not awqare of another means to do so as i may not have set up the builtin iMac remote access features properly.