Hi @william ,
Welcome to TPG Community!
We do not send tax invoices automatically on a monthly basis as we've made it available on your TPG My Account (https://www.tpg.com.au/myaccount). If you require a PDF copy, you will need to contact us by phone or email. Moreover, we continuously work on improving our online account service for our customers. Just PM to us your TPG account details including the date of the tax invoice that you wish to obtain and we'll send it to you accordingly.
In case you need a reference:
How do I private message (PM) in the community