Beko Frost Free Fridge Freezer failing to cool

I've got a Beko Frost Free Fridge Freezer (model number CDA539F) and it has stopped cooling. The temp of the fridge and freezer is around 10degrees!!

I found that the drip tray at the back was full of water. I emptied the freezer and then moved the fridge freezer to be able to empty the water from the drip tray. This is now empty.

I left the fridge overnight to allow gases to settle before switching it back on however it still does not go below 10degrees!! It is continuing to make gurgling noises (like water boiling!?)

Anyone any idea what could be wrong with it?

Thanks

Could be loss of refrigerant or poor pumping compressor. Would need engineer to check