How do I get a proof of purchase

[Boris2021]

Does anyone know how I get a proof of purchase 

[pgn]

Reach out to O2 via Social Media, link just below has the ways, and ask for a proof of purchase - assuming you do not have the contract details in your e-mail if ordered on-line, and it is not in your MyO2 "Documents" section (here: Guide: How do I get to the 'Download Bill' page?) or the paper O2 Shop receipt if ordered in an O2 Shop,@Boris2021.