usps postal denial and disappearance of signed for pkgs

in the last 10 days not 1 but 2 different pkgs suddenly poof , signed for , then just gone to where?4yrs of directing mail and parcels to this single location..not a single miss , yet here in the last days 2 different shippers , both checked in at the post office , and yet not anywhere , though the actual box was there at 1st ..this friday @ 12:49 a box from ups was dropped off with a signature from the clerk with his name showing, Saturday I’m there to get , they say it may not actually be there even as when the clerk signed for the parcel..and they go into quick denial, act confused and as if I don’t have all the information..it never was complicated until these pkgs started disappearing..I’m thinking there are cameras there in that counter area..I’ll request a security check on this , I know it will show the pkg received..they said it may have been mistakenly placed in outbound mail..but that was the same story the last time just before , and I did go that time to the bulk center a mile away to see if that had actually occurred …somethings going completely wrong here…this last pkg had a value of over $205 …when they talk like such idiots the minute you ask how they lose something that they signed for..complet coming after this..I can’t just change to another post office that easily for these screwups , as all my mail and credit cards are connected with this post office location..but really what a bunch of idiots..this other clerk looked at who signed , then said oh wait maybe he was too busy and sent the box back out on the truck , it’ll show up don’t worry..WTF someone tell me how to go after this , eternal ccchitte show at this point