Only you would know if you have updated your phone?
Also, check with the VW garage to see if any updates are available for your car system.
It may be another app that you have installed or updated that is messing it up, so if you get no luck with anything else, reset the phone to factory defaults and try it without adding any of you apps back on at first.
Remember to back up if you do a factory reset.
Depending on what firmware the phone is running there are apps on Play to assist with A2DP connectivity - just search play store.
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
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