These days, every TV has more than 1 HDMI port. So if your fire TV is stuck at the loading screen there might be an issue with the HDMI port you inserted the fire TV in. Try replugging the tv stick in the same port or try another HDMI port. If the problem was with your HDMI port. Changing the HDMI port may solve your problem.
Method 3: Wait For Automatic Fix
If there is some technical glitch or some other unknown problem. Wait for a few minutes, it will go away automatically and you will be able to stream your favorite content again.
Method 4: Try a different TV

If your problem is still not solved, you can try inserting your Firestick to a different TV. There may be some issue with your TV or maybe the Firestick is not compatible with your TV.
If it works on the other TV, then your TV is at fault. But there is most likely some issue with the fire stick itself.
Method 5: Avoid any HDMI extender or ports

Amazon provides an HDMI extender within the box, so if you are using that extender or any other HDMI port extender to connect your fire stick to the TV. Try connecting the fire stick with your TV directly in the TV HDMI port. This will identify if your fire tv stick is faulty or not.
Method 6: See if your software is up-to-date

These days, if you are not on the latest software build, it may cause issues with your device function. So if you can go inside the fire stick menu, try updating the software to the latest version; being on the latest build always comes in handy when you are using the application, which requires modern functions.
If you are still facing the same problem, then you should replace your fire stick as it is not working correctly, or you can try contacting amazon customer support. Make sure to address the customer executive with all the steps you have taken to get out of the problem. They will give you the support you may need.
Conclusion
Amazon FireStick is a great product; when you don’t want to spend some extra bucks on the smart TV, you can opt for the Amazon Fire TV stick. This TV stick runs smoothly on most of the TV supporting HDPC. If your TV is very old, it might not work on your TV as fire stick needs TVs supporting HDPC.