Can't get full screen shot

Hello Forum.

We're using a PTZ-3MP -A31 Dome Security Camera to monitor an elderly family member.  The camera is in their home some 140 mi.away.  Everything was fine, until 10 days ago and now I can only see the small, frozen picture. When I click on the "play" arrow the circle keeps on turning but never show the camera shot full screen.  Help!