Now it's a stuck payment. I don't know if I will ever get my btc.
This is going on, and all it takes is to read stuff that is written in their website. This is written at the top of their "open ticket" page:
In order for us to deal with your request as soon as possible:
DO NOT - Open multiple tickets for the same problem. This will not result in faster turnaround times.
DO NOT - Open a ticket about a particular coin deposit/withdrawal without first checking to see if the coin is in maintenance, or the coin network is currently experiencing heavy load. If so then do not submit a ticket until this is clear (your coins will likely arrive then).
DO NOT - Open a ticket for help with basic trading. If you require assistance relating to trading, please check the forums instead of raising a ticket, particularly this Getting Started guide.
DO NOT - Ask about Level 2 Verifications, we also have a backlog which we are working hard to clear. Please be patient and expect a delay of up to a week.
If none of this applies and you MUST open a ticket, then:
DO - Include all relevant details in your ticket: transaction ID, coin type, amount and date/time of transaction
DO - Be polite to staff, we will not put up with abuse towards staff, they are working extremely hard to clear the backlog of requests and we are training more as fast as we can find them.
DO - Expect a delay in us replying to your ticket, at the moment the wait time is around 5 days.