Government Gateway access code

I've been trying to login to my government gateway account to access the tax free childcare scheme (which I've done plenty of times over the last year) but it's not sending an access code. I've tried to go through the process of changing where I receive the code, but it needs to confirm my identity, and despite providing all the correct information (tried several times), it won't do that either. It says it can't confirm my identity. How can I access my government gateway account now?

Hi,

Please contact the Childcare Service team for advice at:

Childcare Service helpline

Thank you.