Cashaa has incorrectly changed my phone number

[Fonz Ferdinands]

I entered my phone number correctly and received an OTP verification text message on Wednesday, 8 November, 2:24am and correctly verified my phone number.  I checked my account details and then notided that Cashaa has the wrong phone number in the "My Account" section.  My correct phone number is (+61) xxx xxx 076 and the Cashaa has gotten the last digit of my phone number as a "3" ...I have raised 4 support tickets and no-one will change the phone number for me.

The incorrect phone number must be changed but I have no idea how to change it to my correct phone number.