I had some cryptos being staked in the Pools department at Polycat Finance. After the site layout change, I can no longer find the coins.
It seems like that there was a bug and the only best thing to ask people with capability to answer your question. This is ever happened with sovryn dapps in the past but it could be a layout or UI bug. Have they disappeared forever and why? 
They have not but it must be locked in the staking address or contract. Just ask the developers about this because they were having enough capability to answer your question and fix the bug if there was.