I have a M30 smasung model unfortunately after updating my cellphone to android 10 I have faced with 3 major problem:
1- Battery Draing:
I charged my cell phone in 100% at night but at morning( 6 hours without any using) battery charge dropped to 70%.
2-4G internet is missed.
Unfortunately I have only 2G/3G internet or H or H+ internet and I missed 4G connection.
3-Missing Antenna in Dual Sim-card periodically.
After updating to Android 10 my cellphone have problem in Network for example sometime I have to sim-card but after 5 minutes one sim-card will be out of services.
I went to SAMSUNG service center and I saw 20 samsung M30 model with similar problems.
Please debug this very bad issues as soon as possible and send new update for Android10.