Hilton Best Price Guarantee Approved then Removed?

I submitted a Best Price Guarantee claim for my upcoming trip in Australia last month and I received the following confirmation:

We are pleased to confirm that we have now approved your claim. I have lowered the rate on your reservation to match the rate found in addition to another reduction of $50 USD equivalent amount. The current new rate per night after the adjustment is 237.69 AUD before applicable local charges. A new email of confirmation has been sent to you.

After logging in to my Hilton HHonors account, I noticed that my total room rate for the period was adjusted from AUD 2,200 to approximately AUD 1,902 (as mentioned in the email). However, upon logging in today, I realised that my room rate for the Australian property has been adjusted upwards and back to what it was before! I've emailed the Guest Assistance Specialist to check on it and will definitely update on the matter - this should not be happening! Does anyone out there have similar experiences?