It is possible that your Samsung printer uses an older version of AirPrint now deprecated in the most recent versions of iOS/iPadOS.
Check with Samsung Support resources to see if a firmware update is available for your Printer.
Do you have any security Apps (such as Norton) or VPN installed on your iPad? If so, these may be interfering with your iPad's internal routing table - and may interfere with AirPrint/AirPlay/WiFi Hotspot or other Apple services. If present, it may be necessary to temporarily remove such Apps from your iPad - and then perform a forced-restart of the iPad.
Also check check to see if your iPad is using the new WiFi Private Address feature. This feature is intended to provide additional privacy and security when using “public” (untrusted) WiFi networks.
Settings > WiFi > [Your WiFi Network / SSID] - tap the “i” icon - Private Address
The Private Address feature is largely unnecessary for your home WiFi network; if enabled, Private Addressing can interfere with anticipated operation of other devices, such as AirPrint/Airplay. In such circumstances, you may need to disable this feature - and can be enabled or disabled for each individual network.
Use private Wi-Fi addresses in iOS 14, iPadOS 14, and watchOS 7 - Apple Support