Markus...that's very good to hear and good advice!

If I may I'll take it a bit further and tell you what I always do on Priceline stays:

I call the property directly after my reservation is confirmed and ask to have my account number added to my record.

Sometimes they say, "Sorry, this is a Priceline stay and you don't get points." To which I add, "Yes, I know I won't get points, but I do want all the other benefits that my status entitles me to."

I've never had an instance where they refused to enter the number, and by doing this in advance of arrival, I'm often already upgraded when I arrive (they having blocked an upgraded room for me during their early morning room inventory/block assignments).