Since a view days I have the problem, that the freight will not be cleared totally. There is always on crait stucking at the freighter and I have to destroy it to be able to start the harvesting ship again.

Any idea how to fix it?

Sometimes happens, I had to solve the situation the same way as you.

I did it now several times and it seems now nothing stucks anymore. Interesting ...

Happens when the Deposit is full. Either build another Deposit or go work in the Refinery until it clears.

Either deposit is full, or all of your robots are "stuck".