Microsoft Store Refund for o2 Mobile Purchased Content

[GTrotter]

My son logged into his Xbox and undertook a transaction to purchase content with his O2 mobile phone.  A line for Microsoft Store transaction valued at 31.99 (28th February) subsequently appeared on the mobile phone bill which I am financially responsible.   The content was never delivered in-game and as such have attempted to get a refund from Microsoft without success  (several attempts by phone and online).

Whilst I have been unsuccessful attaining a refund can o2 help ?

[MI5]

@GTrotter 

You need to speak to O2 to get a transaction code which you need to give to microsoft to get refunded https://community.o2.co.uk/t5/Other-Products-and-Services/Coronavirus-Covid-19-Community-Help-and-Su...