Cisco 9971 - Error verifying config info. Can't upgrade or connect. Looking for TLV's

I am trying to help guide you to a more appropriate resource for your question as I believe your request for information is outside the scope of this forum.

Neither chan_sip or chan_pjsip utilize xml files to configure them, Nor do they have anything to do with TLV files.

‘Error Verrifiying Config Info’ is not an error from Asterisk.

The Wiki has a article in it that explains the basics of configuring accounts in asterisk for your phone to register against that has an example for chan_sip as well as chan_pjsip https://wiki.asterisk.org/wiki/display/AST/Creating+SIP+Accounts

Here is an example for configuration a phone with inbound registration here for pjsip:

https://wiki.asterisk.org/wiki/display/AST/res_pjsip+Configuration+Examples

If you want/need to use TLS there is an article here that explains how to use TLS with both chan_sip or chan_pjsip https://wiki.asterisk.org/wiki/display/AST/Secure+Calling+Tutorial

Finally there is the PJSIP Configuration Wizard that can be used to easily configure accounts for your phones. https://wiki.asterisk.org/wiki/display/AST/PJSIP+Configuration+Wizard

I personally have worked with phones from a number of vendors, If I have trouble configuring my phone I reach out to either the Reseller I have purchased the phone from or the vendors tech support itself.