ATT trade in problem. Store canceled my online order!

ATT is a mess!  I specifically did everything online so that I didn't have to deal with the people in store.  They are the next worst people next to car salesmen.  I order a new galaxy s23 ultra, I had a s21 ultra to trade in for the $800 credit.  

  So I placed my online order for in store pickup for the next day, I get there and they can't find my order.  After talking to them, they find my order but told me I had to buy it in store that some technical issue alhas occurred.  So basically canceled my pickup order and had me purchase in store for their benefit.  Well the next day, the return box arrived at my house so I pit me samsung s21 ultra in the box and shipped it to ATT.  Fast forward almost 2 months now I had to call ATT to change my address and haven't gotten my credits applied to account so I brought that up.  They told me to call ATT, then after explaining to them, they have me call first net, now I have an investigation case open.  The return department told us that there was only an exploded battery in the box so they credited my account $35.  I didn't even know that you could take a galaxy battery out of the phone.  I'm pretty sure that since my online order said canceled, someone there stole my phone out of the box and replaced it with a battery.  Looking forward to seeing their investigation team catch and hopefully fire this (Edited per community guidelines).  ATT NEEDS TO TIGHTEN UP THEIR WHOLE DEPARTMENT STARTING WITH THE STORES.  Everytime I have gone to the store to upgrade or do anything, they have snuck an extra line onto my account, hence the reason that I used their website to order