After a review of our authorization database, the only merchant with a merchant name like "%adelphi%" was "ADELPHI SUIT" with merchant number of "688101604309 " - I believe this is the hotel in question. You'll have to confirm this. I see approved transactions as recently as 3/25.
Regardless, I could not find any transaction attempt for the PAN I provided in the attachment. Can you please investigate and ensure this merchant accepts cards issued under all DFS/DCI BINs from the below chart: