Since they are packages that require signature, it’s returned to the post office if no one signs for it. Did they leave a slip saying they passed by? Either in your mail box or community office? If not I’d suggest going to the post office and provide the tracking number. They’ll hand over the package. Just bring your id.

I went to the post office a few days ago and for some reason they said they didn’t have it :(... i have no idea what to do now

Idk about you local post office inner workings, but with my post office only holds a package from Japan that requires a signature for a few days. If I not home to sign for the package they usually only hold it for 3-5 days before sending it back to sender. It really sucks because 50% of the time they dont even leave a door tag letting me know they beed a signature. This possibly could be what happenned to you.