Not able to Send Texts on New Samsung A 13 Phone

[Februarycat61]

Just got a new Samsung A13 which is an upgrade from a very old Huawei phone so having to get use to new phone. First problem was sim from old phone was too big so phoned O2 and they sent me a nano sim  put that into new Samsung and managed to get the set up completed, I am not very tech minded but everything seemed to go ok.

O2 said to wait 24 hrs until new sim would work so did that. Had a few texts come through and phone calls all going well until I tried to send a text back it keeps saying "Can't send message with O2 - Error 0" .  Any suggestions please

[MI5]

@Februarycat61 

Check help here Guide: Text Message Tips (not sent or received) 

[Februarycat61]

Thanks I have had a look at the guide and looked on my phone my message centre number is showing as the monthly number and I am on Pay & Go Big Bundle but the number is greyed out so cannot change it and phone number is saying unknown.

[MI5 · Accepted solution]

@Februarycat61 

You were given the wrong sim card.

You have a pay monthly sim and you need a PAYG (they are different).

Go to your nearest O2 store or contact O2 again for the correct sim.

[Februarycat61]

Thanks have just rung O2 and spoke to a helpful lady this time and she is sending me a new sim for PAYG so hopefully will be able to send texts again

[MI5]

That will work fine then @Februarycat61