WALMART RETURN WITHOUT RECEIPT Hilo Hawaii

I don't know really much about law and rights of a customer when bringing in items to return without receipt. I do know what I read under the store policy board right there when you enter the store so if anyone can help me out and tell me what you know I would really appreciate it!!

Several days ago I went into walmart to return several items that was a gift little over a month ago. After a very long time of waiting in line it was my turn finally. After scanning 1 item, they had me wait and wait while in the meantime went in the back room, then called someone on the phone, then brought the item onto the floor and when they came back told me they were going to hold my items until this guy "Jeremy" comes in since he left for the day but would be in tomorrow morning. Confused and furious I asked whats the reason for them keeping it and said because they items I brought in were high priced items priced at $40 each and I did have 4 but also had the receipt for couple of um! Besides for the ones I had the receipts for, they havent sold any other for couple of months. I did say a few things like what right do you have keeping the items I brought in to return, but was told I might be right but shes following what her assistant manager told her.... whatever then
The next day no one called like they said they would so I called and called being kept on hold for Jeremy or any manager that could help me for more than half an hour waiting! Finally again when I tried calling in the afternoon time just my luck Jeremy left for the day but I spoke with a dept. manamger "Rob" which first told me he was on duty when I brought the items to return but had no idea on what happened. No knowledge of the situation and would call me back. When he did he explained that the items I went to return hadn't been sold for a couple of months and if I got it from a different store instead...!?!?! To make a long story a lil shorter is that still til today days later I haven't gotten ahold still of Jeremy, no one still can help me nor will they release any credit or my items back to me!!! Now ok, can some one tell me what the hell is wrong with that!?!?!? I am so furious with wal mart I shop there many years never had a problem like this. Can they just do that? So what if the item wasnt sold for a couple of months...? Isn't there something I can do? I was told they were only going to hold it until Jeremy comes in then he'll give me a call or I can call which I ended up doing anyway since no one called me. All the manager had to say to my question was he didn't know. How can WalMart keep items brought in to return without receipt like I stole them? I walked in to return and walked back out without any credit and without my items! How can that be? Is that right? What can I do?

Lalameda
Pahoa, Hawaii
U.S.A.