> I tried above hotel ..

I meant I tried above URL.

I checked that link and it didn't seem to work properly, I agree. It isn't that it isn't giving you any discount, but not enough. The issue is that the rate shown is adjusted for being a 3 day stay, it is below the normal rate. But it isn't enough below to give you one night free. I tried the same dates minus one day and the rate on the 3 for 2 is definitely cheaper than if you only book two nights, but not enough. For two nights, I got 175 euro per night for a classic, for 3 nights it was 156 euro per night for the same room. But that doesn't give you one night free, just at a much cheaper rate.

So I do think you have to contact the hotel. I've seen a lot of that software online for Paris hotels and have gotten those kind of rates with no problem in other hotels, so it usually does work.

Bookmarking.