There are many reasons your internet might be unstable. Please check the tips below:
If your router is on the floor or in a corner, the signal will be weaker. Place it in a central, open area of your home.
If all router antennas point the same way, the signal can drop. Set one antenna vertically and the other horizontally.
Metal, walls, and appliances can block Wi-Fi. Don't hide your router—keep it in an open space.
Routers that have been on for a long time may get unstable. Turn it off, wait 10 seconds, then turn it back on.
Other apps or programs may be using your internet. Close unnecessary apps running in the background.
Your home layout or distance from the router may weaken the signal. Run a speed test, and if needed, use a LAN cable or a Wi-Fi extender.