Level 1: Cadet

SMS error 21

I've never experienced this problem whilst sending my friends an SMS or a call, I have service, bought a new phone as a solution which didn't work and I know for a fact that my number hasn't been blocked. Please help.

I can chat through whatsapp still.

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Level 25: The Singularity
Level 25: The Singularity

Re: SMS error 21

That means that your phone is dropping the network connection and can take a few attempts to get it back up and running. Putting your phone into Airplane mode for about 30 seconds and then disabling Airplane mode will usually fix it on the first attempt.

Never be afraid to back yourself when trying new things, just always make sure you have 3 escape routes if things go wrong.

Set it & forget it

With direct debit there’s no need to give paying your bill another thought.

Avoid queuing up and never worry about late fees again.

Setup direct debit