I don't think you ever described your environment, that is, do you have other receivers involved such as Joeys? If it were me, I'd try this as a start:
1. Go to the dish antenna. Unplug any coax attached there that does not go to your Hopper 3, if you have connections to Joeys. ("Client" port(s) to Joeys)
2. Use a new piece of RG6 coax to connect the antenna to your Hopper, no other devices connected on the network. ("Host" port to Hopper.)
3. If you have an OTA adapter on your Hopper, unplug it from the Hopper.
4. If you have external drives, unplug them.
5. Go to Settings - Diagnostics - Whole Home and see if the link status says Strong.
6. In Settings - Diagnostics - Status, check MoCA status and see what the result is.
With the simplest configuration, see if you keep getting resets. If not, start adding back other devices starting with Joeys if you have them, then EHD, then OTA adapter if you have it.