@Bewillis23
The flashing LED on the Streaming Stick usually indicates a loss of network or internet connection. Since you are also having a problem getting the Roku remote to work, it could be an issue with the LRWR (Long Range Wireless Receiver) cable.
The LRWR is responsible for both network and remote communication on Streaming Sticks 3810 and 3820.
Try unplugging everything and reseating all the cables. If you are currently using the TV USB port for power, try plugging the USB-A end into a power adapter at the wall outlet. (any 5volt, 1amp cell phone charging adapter should work).
The Streaming Stick models are the only devices that require this proprietary cable. The other Roku models no not need this cable as the wireless module is contained inside the device case, rather than within the power cable.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102