Reckless lending

I cant understand how ones application for credit can be declined months after it has already been approved, this doesnt make sense and ur advisers are not capable of explaining this. The facility has been approved and a purchase has been made, payment has been made ever since. I havent defaulted and even contacted to provide new banking details to ensure payments are made on time. If that is the case then is this not considered as reckless lending? An affordability check was done if i am correct but why are they only declining my application now?