If this does not help I recommend letting a service technician have a look. As we would like to gather additional information, and look at this from a case by case basis, please provide the full model code and serial number of the device as well as your best contact phone number, name, and email.
Try running the diagnostics available here in the Members app in the Support tab and see what the results are. Another option would be to take your troublesome tablets to someone else's wifi network and see if things work any better on another network. Possibly your wifi router has a problem.
Back out of this conversation in the app and and you should see options Discover, Community and Support. Select Support and then you will see Diagnostics where you can either let everything get tested on your tablets or have it just run its Wi-Fi diagnostic.
Try this Reboot the Router: Unplug your Wi-Fi router for 5 minutes, plug it back in, and try reconnecting. (Sometimes the router just needs to drop old cached IP addresses).
Forget the Network & Clear Cache: On your tablets, go to Settings > Connections > Wi-Fi, tap and hold your network, and select Forget. Then, go to Settings > Apps > Wi-Fi > Storage > Clear Cache before reconnecting.
Disable \(5\text{ GHz}\) Temporarily: Log into your home router's admin panel and temporarily turn off the \(5\text{ GHz}\) band, leaving only the \(2.4\text{ GHz}\) band active. Some Galaxy tabs only like connecting to \(2.4\text{ GHz}\) upon initial setup. Once it connects, you can turn \(5\text{ GHz}\) back on.
Reset Network Settings: Go to Settings > General Management > Reset > Reset Network Settings. This wipes out all saved Wi-Fi and Bluetooth profiles, giving you a completely clean slate.
Change IP Settings: When entering your Wi-Fi password, tap Advanced or the gear icon next to your Wi-Fi network. Change IP Settings from DHCP to Static, then assign a manual IP address (e.g., matching your router's setup
If this does not help I recommend letting a service technician have a look. As we would like to gather additional information, and look at this from a case by case basis, please provide the full model code and serial number of the device as well as your best contact phone number, name, and email.
