Long story short:
Doing a fuel purchase on an automatic gas pump requires a covering funds reservation on the card. Using Skrill card for fuel purchase means they make a 100 euros reservation on the account no matter what amount you request. I have used the card for amounts like 20 to 90 euros and yes, that's how it goes. And the customer support has confirmed it to be the policy, always 100 euros reservation (at least when the amount requested is less or no more than 100 euros).
Many times it has gone well. Fuel purchase of 20 euros, 100 euros reserved for 3 days, on 3rd day after the purchase the payment is settled and the remaining reservation released. That's how it works with Skrill, also confirmed by the customer support.
On 2nd of July I made a fuel purchase, requested 60 euros reservation, used 50.08 euros of it, drove on.
On 5th of July the payment was settled and the amount of the purchase, 50.08 euros, was deducted from my account. The reservation of 100 euros remained, as a pending transaction.
On 8th of July I opened a service ticket in the Skrill app, asked about the remaining reservation.
On 9th of July I got a reply to that ticket, that the issue has been resolved. And yes, the pending transaction, reservation of 100 euros, disappeared from my account. The problem is that I got only 40 euros back to my balance.
Ever since I have been trying to ask about the case from the customer support. More than the loss of 60 euros I get annoyed by the inconsistency of the customer support. In most of the answers they are denying the manual release of the reservation, just copy pasting the standard text how the process goes. One customer support representative though admitted in email, that indeed, the reservation was manually released on 9th.
Couple of them have been insisting that there never was a 100 euros reservation. I have screen captures saved of all the events and messages. Reminder, the customer support has confirmed, that they always make a 100 euro reservation. Yet there was one person claiming, that there was a 50 euros reservation which was released automatically on the settlement of the payment.
I was offered 10000 knect points for the inconvenience. That's worth 10 euros.
I have contacted the Central Bank of Ireland. Maybe it helps, maybe not.
Ps. they did same kind of thing last spring. I bought flight tickets with Skrill card and the amount was reserved at the time of the purchase, the payment settled on 3rd day after the purchase, but the pending transaction, reservation of the amount, remained, and it took a whole month for them to get it solved. I received 10000 knect points for the inconvenience.