Adyen offered & requested more info about {T359977} where an internationally-enabled Maestro card was blocked. I append their full comment below, but the info request is:

"Could you share with me the JSON request and Response for the API /checkout/v68/paymentMethods using the country RO? So I can narrow the behaviour?"

Could someone in Fr-Tech look at this to provide an answer to this question? Are they just asking whether Maestro is included in the card brand list?

Adyen Case 03667389
Thanks for confirming that you are not making an extra validation on your end.

Another option I was researching this could be happening is due the JSON Response to /checkout/v68/paymentMethods did not include Maestro transaction variat for the country Code RO being Romania.

I tried to search one request with the Country RO on the Logs.

Searching API Logs

Could you share with me the JSON request and Response for the API /checkout/v68/paymentMethods using the country RO? So I can narrow the behaviour?

For example this request:

{

"merchantAccount" : "WikimediaDonations",
"channel" : "iOS",
"countryCode" : "US"

}

Includes Maestro as a Brand:

{
       "brands" : [
          "visa",
          "mc",
          "amex",
          "cup",
          "diners",
          "discover",
          "jcb",
          "maestro"
       ],
       "name" : "Credit Card",
       "type" : "scheme"
    },

In case Maestro was not included in the response, it could not be used on the Checkout Session.