Payment rejected by payoneer without any reason!

I have 3 consecutive payment rejected cases.

1. Buyers are all my years old buyers who purchased and paid previously at least 4 times via paypal for ebay sales.
2. so many consecutive rejected payment threatens my sales and business
rejection is not from payer's bank or credit card but directly by payoneer.

CASES
1)
Payment Request ID: 1002286,
Status: Payment rejected. Payment Declined,
Declined On: 17.7.2016,
Paid with Credit Card
Country Australia
related payment Id 28259341
2)
Payment Request ID: 999001
Status: Payment rejected, Payment Declined
Declined On: 17.7.2016
Paid with Credit Card
Country USA
related payment Id ID28346090
3)
Payment Request ID: 1000336
Status: Payment rejected, Payment Declined
Declined On: 14.7.2016
Paid with Credit Card
Country USA
related payment Id 28180520

question: WHAT IS GETTING ON?what is the reason for payment rejection for each case? I am really in trouble. I cannot keep my clients upon so many payment rejections. they do not have to struggle with payoneer problems, they just will go away and buy from other sellers possibly paypal accepting ones?
PLEASE HELP IMMEDIATELY.
it is not possible to reach live chat in even working hours. payoneer help became like a deaf wall.

(I am a seller in etsy as well and I am watching some issues with their own payment system though irrelevant to payoneer. Etsy direct checkout keeps rejecting and causing problems for buyers and seller processing payment. I reminded me
etsy direct checkout may use in fact payoneer in background. not sure but if it is not so, is there a general problem in payment processing??? in markets)