Payzapp — unable to load amount. payzapp blames banks for this

I am using payzapp for online transactions since a long time. As we know payzapp allows loading of money in to pay zapp card only through debit/credit cards. I have added 2 cards to my payzapp wallet. One of icici and second bank of india. I am trying to load money to my payzapp wallet for last 10 days. I used both the cards (Icici & boi), but every time transaction gets failed with the use of both the cards. I contacted payzapp customer care and mr. Sadiq from their customer help desk replied me that it is the problem of banks and not of payzapp. I am successfully doing all transactions with both the cards at other shopping outlets and wallets. The problem is only with payzapp. I uninstalled payzapp and re-installed and tried but the same problem exists. Payzapp is not answering to me. I believe payzapp is not going to wind up and close the app. I am not getting help and solution to my problem. Expecting a solution to my problem through this portal.