GFCI Test button is intermittent
Those are counterfeit GFCIs
I would chide you for being &quot;cheap&quot;, but the fact is, many of the dangerous or counterfeit items on Amazon are being priced same as quality items.  Further, counterfeiters have found an exploit that gives you a fake even if you order a &quot;Ships from and sold by Amazon&quot; item.
As a result, do not buy electrical equipment on Amazon..... and I gather I don't need to tell you not to buy it on the other shady mail-order sites like eBay, Banggood, DealExtreme, Wish, etc.
Jeff Bezos is firmly committed to making Amazon a &quot;platform to connect sellers to buyers&quot; - in other words, eBay. Further, Bezos has thrown open Amazon's warehousing/fulfillment/delivery system wide open to any comer.  Industries use it, eBay sellers use it, and if the item is also sold on Amazon, it ships with Prime.
So it's a gory mess, and it's impossible to give any guidance as to how to buy on Amazon safely.  Best advice: don't.
They all need to be ripped out
.... sent back and replaced with ones from a competent home store.  Send. Them. Back. Don't you dare let the counterfeiter keep your money! I know most consumers don't bother with refunds in most cases, but please do with counterfeits - it deters counterfeiters and helps Amazon identify the bad guys.  If the return window has expired, call up Amazon - they're more reachable than you'd think, and yell and scream - you'll get it.
If you don't want to walk into a Home Depot, they and Lowes do curbside pickup, and both will happily mail-order for you, and they ship it from their own supply chain, which are under quality controls.
because aside from being unsafe, they're not legal. NEC 110.2, equipment must be approved.