Have you tried another SIM card in your device? Have you tried resetting the network settings? Just as a heads up resetting the network settings will remove any saved Wi-Fi networks and Bluetooth devices that are paired with your device.
I had this problem with 4G LTE not working properly. Everytime need to restart than the 4G working again. My Samsung S10 plus set is purchase in Singapore 🇸🇬.. Hope Samsung can sovle the problem. I send to service centre they say nothing wrong. Is very hard to convince them because the phone is not with them all the time.
We would recommend reaching out to your carrier directly who provides your mobile data, as it sounds like you are experiencing issues with your mobile data.
This is for sure a Galaxy S10 issue!! Samsung had a bad patch, I'm sure of it. I was on Sprint, same issue (Bands 2 and 4 do not work on my phone) moved to T-Mobile same issue. I had to turn off bands 2 and 4 and things work. you spend $1000 on a phone that is inadequate!
I have done everything tech support has asked of me and still the problem is still there.
I have run multiple test and bands 2 and 4 do not pass data. I even will have 5 bars and it will not pass data.