Safari Major Issue

I at first noticed that I could not open Safari over a week ago. I tried to restart my Mac mini but after clearing applications it would not restart. I restarted by holding in on the on/off button. After this restart Safari runs, but for less than 24 hours. I have made these observations:

• “Force Quit” has no affect.
• After a period of time Safari disappears from the Acitity Monitor list, so I cannot force quit from there.
• If I right-click Safari in Launch Pad, I get this pop-up message:“The application “Safari” is not open anymore.”
• If I “Get Info” on Safari I see Last opened: March 10, 2019 at 3:17 PM (today March 24) even though I restarted (holding button in) for about a week.
• Again, once Safari halts, I cannot restart or shutdown by software.

Help!