Since the last DCS release (not sure at 100%), it's not possible to select some airfields in persian gulf. It looks like some airport have been renamed.
I.E. with Al Minhad: it seems to be "Al Minhad AFB" on the map, and vaicom is looking for "Al Minhad AB":
Captured sentence: al minhad
Have result, identified as recipient: Al Minhad
(awaiting additional input)
Captured sentence: select
Have result, identified as command: Select
Searching called unit Al Minhad AB in category ATC
Recipient Al Minhad AB is currently not available.
Can someone have a try ?