Calls and texts not working

[#1]

As above really.  There seems to be no way of resolving this online.  I need my phone to work and it gives me a phone number to call but I cannot make outgoing calls or texts to do this.  Nor can I receive any!  Am I missing something obvious here?

[#2]

Borrow someone else's phone?

If you "need" your phone for your work, and cannot do without it, then what was your backup plan? Technology does have a habit of failing at some point.

Have you tried restarting the phone or trying the SIM card in a different phone?

[#3]

I arrived in Malaysia yesterday for holidays. I can’t send or receive texts. I would be grateful if someone can help me resolve this problem. I have a Samsung Galaxy A21s phone.