Turn off your Computer, turn off your router, turn off you Internet modem. Wait 30 seconds and turn on your modem. When the modem is showing normal lights, turn on the router. Wait for the lights on the router to normalize and then turn on your computer. Only then should you open StreamFab.
Cats4U
One minor two-cents addition to this part.... Windows by default has "fast startup" enabled, meaning a reboot clears your memory, but a shutdown saves your memory state to hard drive, so that does not clear your memory and achieve the desire effect you are pushing here. You can disable this computer behavior in your power settings. Without posting a book, google "disable fast startup windows 11". Ironically, fast startup enabled takes longer to boot on average because in addition to loading your OS, it's loading your complete memory state from the last time you shut down.