Has anyone encountered this issue before when using SYW card to buy gift cards in a gas station?

I just got the card about a month ago and wanting to buy gc to meet initial sign up offer because I am really busy this few months.... I had a $200 amazon gc purchase from Speedway 5 days ago which was approved. Then I had a $400 amazon gc from Safeway 4 days ago which was initially declined but later approved.

Today I went to Speedway to buy $900 amazon gc to finish the rest of the spend but it was initially declined twice. I called the cc company and they claimed that they cleared the card. Tried $900 charge for the 3rd time and it was declined. CC representative said try again, I then tried again $900 for the 4th time and it was approved per cash register only partially for $500 (I have a $5000 credit limit so not sure why only partially approved...). After trying to figure which of the gcs were actually activated, I then had the clerk charge again for the remaining $400 amazon gc, it got declined again by the store but per cc representative, it went through. We tried again for $200 amazon gc, it again got declined by the store but the cc representative said it went through... CC representative was not able to tell me if the charges were the actual charge or just on hold/pre-authorized charges and I waited over 1 hour to be transferred to different department/supervior without a clear explanation other than that "the charges went through okay.."

Per store cash registry machine:
$900- declined
$900- declined
$900- declined
$900- partially approved for $500
$400- declined
$200- declined

I guess I should have stopped trying earlier to avoid this mess, but I really didn't want to come back to the store again to deal with this, so I just had them keep trying...

Now when looking at the online portal, I saw the remaining credit decrease by the amount of $1500 (matching what the cc representative said that the last 3 charges of $900, $400, and $200 went through ok.) BUT in the end, I only got the total of $500 worth of amazon gc because that's what the store actually approves the transactions per the machine message.

I did have them print out receipts for the last 3 transactions showing that in total I only received $500 amazon gc while the rest was declined. I think maybe the store had some sort of scam/protection mechanism built in after so many declines so they only restricted me for $500 total and the rest were just "on hold"/pre-authorized, not the actual charged amount? I hope the charges will eventually show up in SYW card transactions correctly after a few business days... Anxiously waiting for that.

Has anyone encountered issues like this when using SYW card, Speedway or while buying gift cards or with declined charges in general?