You didnt mention your Roku model # and firmware version: Settings/System/About
Known solutions/workarounds for apps not loading/closing to Home:
1) Check for updates: Settings/System/System updates/Check now - try again
2) Change your Theme to the Roku Default: Settings/Theme/Restore default theme - try again
3) Change your Screensaver to a Roku clock: Settings/Theme/Screensavers - try again
4) Remove SD card (if installed) - try again
5) Remove app, RESTART ROKU: Settings/System/System restart/Restart, Add app - try again
6) Network connection reset: Settings/System/Advanced system settings/Network connection reset - try again
7) Completely unplug power from Roku for 10-15 minutes - try again
😎 Factory reset: Settings/System/Advanced system settings/Factory reset <--- last resort
NOTE for #5: Do not remove the YouTube TV or Spectrum app - you will not get the app back until the end of the dispute.
Otherwise, as @atc98092 suggests, it may very well be a hardware problem, and you'll need to contact HiSense support.