I had a bit of a problem in one of the lounges in AMS last year. I had left the lounge found a different lounge dragon sitting at the desk when I came back in. Although she spoke very good English, the dragon had a very difficult time understanding that a) I had already been granted lounge access and b) My priority pass was "just in that bag on the chair over there". Fortunately, the lounge dragon who'd originally granted me access put in a special guest appearance and intervened.

If you're on a standard Priority Pass (in other words, you pay to get in), always take your Priority Pass and receipt with you if you must leave the lounge for any reason.

Regards
I