Unable to use staggered payment function and ZERO customer service

.Tried on multiple occasions to utilise this payment platform for their “interest free” staggered payments but on every checkout attempt I get “YOU HAVE AN INSUFFICIENT SPENDING LIMIT. But we have a solution for you. Please pay the full amount today using any payment card.”

Obviously If I wanted to process the full payment amount for a purchase I would do just that, so this is not a solution?

What further disappoints is the complete lack of customer service. Even if you report this and request assistance or some type of clarity they either don't revert back or tell you to “Please focus on the instructions on the Payflex screens”