Issues redeeming Velocity points on mobile devices - does it mean bookings must be done on pc?

I made a booking on delta using velocity points, filled out all the info then it told me to contact guest services.

I did to complete the booking and I got stung 9000 points x 4 for doing booking over phone, they told me I can’t make points plus pay on mobile devices ???

Mind you 3 out of 4 guests are platinum members, not very impressed.

Can any one tell me where on velocity or virgin it says making points bookings must done on a pc !?

It says it at the bottom of the mobile page.

You can book it from your phone, but you’ll need to use the ‘full site’ to do so.

Understand, but I was on the full site on my mobile ?