I have the same experience .Several of my packages were delivered to wrong address. I did contact 1-800 number.Still waiting for Old Hickory Post Office to respond.
I have had several packages never arrive. Last summer, with a substitute carrier, a package of expensive, compounded medications was delivered to the wrong house and did not get to me until weeks after I had repurchased the medication.By then, the original were out of date and had to be destroyed. It cost me over $600.00. The local poat office personnel were polite and appeared concerned, but I believe they did not believe me until I had a tracked package just disappear. Warning: If you do have something delivered by USPS, be sure to pay extra for track and confirm. Then, maybe, they might believe you.