I had that problem last year and guess what – I had to get another feed box! I think it depends a bit on how many leaves they’ve taken in and if they continue to. If there are only a very few and no more go in, I might take them out, but the one here took loads in and continued the next night, making a very elaborate nest, so clearly had to be left to get on with it.
If you can, I think I would be inclined to make another feeding station and see what happens with the other one. It’s always handy to have a spare!