Very Account accepted / declined

Hi guys,
It is the first time i am using Very and i needed some input on the matter.

I opened up a credit account yesterday to buy the LG G5 and it went through. I received and email confirmation with £600 credit limit

However, today i received another email stating that my order was cancelled and my credit balance went back down to zero.

Yesterday i tried to pay for it using debit card but mobile web didnt have the option so i couldnt.

Can they do that? Do a credit check, accept and then suddenly reverse and decline it the next day? I have an email confirming the credit of £600.

I am very confused here...