@Roy *******
sincerely think the OP has his wires crossed and using the wrong vocabulary and terms:
Thai Customs (ศุลกากร) ?? or American Customs (DHS CBP) ??
OR, do you mean Thai Immigration (ตม) and American CONSULAR Officials (กงสุล) at the U.S. EMBASSY in Bangkok or American CONSULAR Officials (กงสุล) at the U.S. CONSULATE in Chiang Mai ??
Thai Immigration (ตม) at the local (Provincial/จังหวัด) Office or Thai Immigration (ตม) at the Airport or Border Gate (ด่านพรมแดน)
Again, several have already commented that Thai Customs (ศุลกากร) and American Customs (DHS CBP) have nothing to do with passports, visas, immigration, citizenship: thus, probably wrong usage of terms by the OP, but is confusing everyone....