First read carefully. Banks mould information to lure customers. The photo you've attached is saying this card 'WORKS' as credit card. It's not written anywhere that this card 'IS' a credit card. There's a difference between these two statements.
Moreover go through the photo I've attached from RBL website, its clearly written that this is a unique 'CREDIT LINE'.
(I'm attaching the link for your reference. Its actual RBL BANK website where this is written.)