MSI Shout Out Codes Are Not Valid

I took part in the MSI Shout Out campaign, and as a reward, I was given a Steam Wallet Code worth 500 TL. On Monday at 8:31 a.m., the codes were delivered to my email inbox. I couldn't contain my excitement, so I entered the codes right away. On the other hand, I got a notification that said, "codes have already been used." In the email, it was stated that I was to get in touch with customer service if there were any problems with the codes. It would appear that there is no customer service available, which is very unfortunate. I have been unable to get in touch with customer service, and the issue still stands. I earnestly demand that this matter be resolved as quickly as possible.