Can I transfer my Apple account balance to Apple Pay

Contact iTunes Support to see if they can/will do that for you. See the Apple Support articles below for contact information.   

iTunes Support – world wide 

Apple Support schedule phone call      

If necessary, try Twitter

https://twitter.com/AppleSupport.          People have posted it may take an hour or more to get a response.

Hi Hghhhhufjgf,

We understand that you're wanting to know if your Apple ID balance can be transferred to Apple Pay. We will do our best to explain.

You add a credit card, debit card, or prepaid card to the Wallet app for Apple Pay, however there isn't an option to transfer your Apple ID balance.

If you would like to submit feedback and/or suggestions about this, you may do so here: Product Feedback

Take care