No signal

[Benjamin24]

Since previous update I've had no mobile network coverage and then another update now phone seems take longer to charge and still no network have lost work and all sorts of problems not happy considering the phones is meant to be 1.600 £ I've got Sony Ericsson at moment full signal so old it's small pics plastic charger connection etc fantastic more reliable than an apparent 1.700 £ phone wellmdone Samsung 

[BandOfBrothers]

That's not good @Benjamin24 

Here are a few generic tips you could try.

If they don't work then seek support from a Samsung Experience Store  / Samsung Service Centre 

1. Settings, General Management,  Reset, Reset Network Settings. 
2. Clear your System File Cache vai the instructions in the Samsung Link. You may need to hook upto a computer or insert your headphones to get to the recovery menu. https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ 
3. Back up and Factory Reset as a very last resort.

[AlexRo]

I tried all this. I will go at Samsung service 3rd time today... for this time I will leave device there... ***** samsung

[Rūmøur]

You arent the first to experience this. People have been experiencing this issue on their s21 ultra since the July security update and its still not been fixed. Do you have a 🚫 sign showing in the signal area? Can you post a screenshot?

[Rūmøur]

Amy update??

[Benjamin24]

All sorted replaced phone