How can I prevent unauthorized purchases on my lost credit card?

On August 19, 2024, I forgot my wallet on board a United UA34 arriving at SFO airport.

Inside the wallet was my apple credit, which was lost along with the wallet.

I told United Lost & Found at SFO that I had lost my wallet around 1:00 p.m. that same day and they checked it out, but they could not find my wallet.

I have not received any further notification from United that my wallet has been found.

Then, on August 23, 2024, at approximately 2:00 p.m., I received a notice of an unauthorized purchase using the Apple card I had in my wallet; the purchase was not completed because the Apple card had already been deactivated. However, this fact suggests that whoever picked up my wallet initiated the purchase without notifying the police. In other words, it indicates that my apple card may have been stolen as well.

[Re-Titled by Moderator]