Why can’t I pay for comp entries like I used to with o2 ?

In particular the travel shows .

Do you have credit on your account davowolf? competition or premium SMS are not part of any free minutes or texts.

So is there any way of using my phone with Lebara to enter these comps as I did with o2 ?
Thinking it may have been a solution I just actioned from within the Lebara app, a top-up amount but haven't tried it yet.

Lebara doesn't offer credit you pay everything up front.
Anything that requires money must be paid for up front.(Top up)
You must add money to your account in advance.

Superuser25 Understood thank you and will do .....