Price and voucher?

Trying to buy a solid wood door on the BWH website and found a door that my wife like and the price not to bad. I received a birthday discount voucher a week or so ago which was for 10% discount (on Wednesdays I get pension discount of 10%), nothing serious but with the current financial state any little bit helps. What a shock to see the price jump from R2599 (Advert) to R2999 (Checkout) then I tried the so-called birthday voucher and as per current SA it has already been claimed. Don't know by whom as it's been some time since I've bought anything at builders. People should be aware of the fact that the advertised price is not the same as the purchase price. Even though it's a noble thought to give registered members a special birthday voucher but it means nothing if someone else has used it before you've even tried.