Payment Assistance
Double conversion - the amount of the donation selected in a currency that does not correspond to the currency of the card. Double card conversion is usually disabled on the card, so the acquiring bank cannot convert your money into the desired currency.
You can enable double conversion in your card settings on the bank's website, application or hotline. The amount of the payment may be slightly higher than the set amount of the donation.
Online payment limit exceeded - the limit for online transactions has been set on each card. This limit may be zero, in which case online payment by card will be prohibited. You cannot spend on online payments more than the set amount. At the beginning of each month, the limit for online payments gets updated.
You can change the limit for online payment in the settings of your card on the bank's website, application or hotline.
Card limit exceeded - you can exceed the limit for donation, or the number of bank transactions per day, or the total money transfer limit per day.
If your transfer has failed, you will receive an email letter, in which the reason for the rejection of the transfer will be explained.
Non-sufficient funds on the card - check if there is the required amount of money on your card.
PayPal
Монобанка
Wire transfer 
Cryptocurrency