was denied the sale of a marked down item

To whom it may concern<br> I was denied the sale of a marked down item at their reduced to go sale. It was a Sony shock 44d I have photographic proof that it was marked R2990 when I queried it they repeatedly said the 2 was actually a 7. There is absolutely no chance that it was a 7. The manager then continued to say the sticker was tampered with due to R2990 previously being written as R2999. I find this to be extremely wrong and false advertising was committed here. I also feel I was disrespected and not taken seriously just because I am young (I am 19). this is not right