What color is your serve card?

green

At money center / customer service desk or regular terminal?

at money center.

Reward checking Lending tree checking doesn't work, does Upgrade?
 

Any datapoints if UPGRADE checking rewards work for loading with serve online? I tried with LENDINGTREE checking and didn't receive anything, even though I had 2500 average balance for May, and received interest in the account.

This is crazy stuff. Why are they charging for serve load at MC when it is supposed to be free?

God knows. I canceled the tx and left.

You didn't complete the transaction but it would have failed anyway because Staples VGCs are serviced by BHN and are limited to $99/load at the CSC/MC.
The new charge for BB cards does not come into effect until 7/1 according to my emails from BB and BBVisa. I have not seen anything about a charge for Serve at Walmart but this reminds me of the change that came into being with Go Bank. They instituted a charge several months prior to the actual published time of its actual institution but it was refunded when the problem was brought to their attention.
Of course, Go Bank did go through with the charge eventually, so maybe this is a harbinger of things to come :o

GC that I have from staples from shows Metabank in the back.

Metabank is the bank that backs the card financially.
BlackHawk Networks (BHN) is the servicer of the card (think back office provider).
Cards serviced by BHN have a $99/swipe limit at WM for loading or MO purchases when done at the CSC or MC. However, at the cashier, one can load a BB or Serve card to the max of the card (for Staples, it is $200) with one swipe.
So, to make this clear, if you take your Staples card to a cashier, she will be able to load your BB card to the maximum of that VGC ($200) whereas if you took that same VGC to the CSC, you would be limited to $99/swipe for loading.
Hope that I was clear :)

yes that’s clear. Still I don’t understand why they tried to charge me for serve reload!?!?

Pretty sure I've tried several Staples Meta/BHN VGCs and have never been able to load the entire $200 into Serve/BB since Jan 2023. They were always smaller amounts under. Usually I have tried $95 and $99. In some random cases, I have been able to do $105 loads but that had been an exception to the time rather than the norm.
Edit: I'm in Nassau County NY if it helps

Out here in ol' flyover country, the cashiers are grizzled veterans who can load a Serve, BBAmex or BBVisa card with nary a blink of the eye for the full $200 in one swipe.
Never tried $500 but that is because I would get the hairy eyeball putting that much money on a Serve/AmexBB card.:o
I have to live with these people :D

Consider yourself lucky. Most folks do not share your experience with Staples VGCs that you do at WM Cashiers.

denied two times today when I tried to reload Serve with Staples Visa gift card at Walmart.
Amount I tried was $200.