I have just tried to contact Boots Customer Care ( number was on the receipt) re the App and two different Advantage cards I have - I wanted them to be linked together so I could dispose of one and the card then linked to the Boots App.
I kept getting options of numbers to press which brought me right back to the start again......... and again.
I gave up.
I'm not good with technology and wanted to speak to a human who could help.
None available, unfortunately.
As Jim Royle would say "Customer service my ar*e" 