DHL Promises Next-Day Delivery to Germany, Then My Package Goes Missing

I applied to the DHL Şehitlik branch on 06/25 to send a package to Germany as quickly as possible. I was told that if I paid €59, my package would be in Germany the next day. Trusting this statement, I made my payment and handed over the shipment with tracking number 951937179203.
However, days have now passed and my package still hasn't arrived at its destination — I can't even get clear information about where the package currently is. When I asked the branch, I wasn't given a satisfactory explanation. Since the delivery promise given to me wasn't kept, I've suffered hardship in terms of time, and today, even though it's the final deadline for my transaction, I'm facing a serious problem because my package still hasn't arrived.
I am requesting that DHL first urgently deliver my package to its destination, and that I be refunded the €59 I paid due to the delay and the false delivery promise given to me. I also want a clear, written explanation as to why my package wasn't delivered on time.