cex.io got my money trapped in bitcoin for weeks

cex.io cost me a ton of money because during a transaction, their system determines what transaction fee to use, and it is "supposed" to look at the going market rate to put you in a reasonable position in the blockchain queue. However, they used a tiny fee for some random reason on one of my transaction, 50 sat/byte when the market rate was 500 sat/byte. As a result, my transaction was at the bottom of the queue and stuck 'in limbo' for several weeks while bitcoin was plummeting and I lost a lot of money which I had no intention of keeping in bitcoin. The only way I got my money out was paying more money to a third party accelerator service. Don't trust cex.io with your money.