Regardless of your carrier, if your S10 is still experiencing sudden (and persistent) connectivity drop-outs in seemingly strong signal reception areas, contact your carrier or visit one of their repair centers to have your device tested (Sprint, for example, can test for mobile data connectivity hardware failure at their repair centers) to find out if you're dealing with a faulty/defective device. UBreakiFix is authorized to repair/diagnose Samsung products, so if you have one in your area that is an option as well.
In many (if not most) cases, software will be the culprit. Always test the device in Safe Mode (press power button then hold down power-off icon to bring up Safe Mode) to rule out 3rd-party apps as the problem. Wiping the cache partition (go into Recovery mode - power off S10, power on pressing the volume up + Bixby button + power button until Recovery loads) will also help resolve various issues that can affect the stability of the firmware. When all else fails, a factory data reset will wipe the slate clean and help narrow down hardware vs software problems. If you back up to Samsung Cloud or use Smart Switch to back up data to a PC/Mac, running a restore after factory resetting is fairly simple (and relatively fast) and will bring your S10 back to the state it was in when it was backed up.
Just FYI, a Sprint repair facility diagnosed a hardware failure in my S10+, but Samsung insisted that I bring it to Ubreakifix, who insisted that the phone just needed to be reflashed. It was a hardware failure that required a board replacement. Ubreakifix was useless in my case and caused me to waste more time.