My guess is the ATMs that you’re trying to use aren’t chip & pin enabled.
If you’re an iOS user, with the latest version of the app, you can temporarily enable magstripe withdrawal support -
Magstripe ATM withdrawal support
In the UK, almost all ATMs use chip and PIN to validate your identity when you try to withdraw money. However, that’s not always the case elsewhere around the globe and in many countries, ATMs use the magnetic stripe on the back of your card to dispense cash. Up to now, we’ve disabled magstripe ATM withdrawals to protect against the increased fraud risk that these ATMs bring but from today, it is now possible to temporarily turn on magstripe ATM withdrawals for 24 hours. You can access the setting from your Profile or from a transaction that’s been declined by a magstripe ATM.
Text from this blog.
If that doesn’t work, then as Ian says, contacting support is the best way to get this resolved.