We are out of Thailand at the moment and Madam had trouble paying 3BB so I said I'd do it.

Tried to login but KBank said wrong PIN.

Tried it until they locked me out.

I know it is the correct 6 digit PIN.

What's the problem?

Using a phone app ???? perhaps you don't have international roaming ?

too late now if they locked you out you'll have to phone them or wait till you get back to Thailand to in go to a branch.

36 minutes ago, carlyai said:

What's the problem?

Biometrics, Face ID required.

This is obviously a technical question that requires an answer from KBank.

Give them a ring. Within the app there is a way to ring a helpline through the internet, but since you cannot access it now you will simply have to ring their number the normal way: 02-8888888.