bothead

I use Zombaio and am experiencing 80+% of new signups being declined transitions code 5 (whatever that means)
Is this normal? From what I can see if they are getting to the zombaio age and entering their CC details... 80% rejection seems very high. especially when we started last year that figure was about 20%.

Any suggestions or insights on this? is that a processor issue.. it seems weird to me that 80% of people using a credit card have it declined by the bank.

Thanks in advance for any helpful pointers