you can still send 90 day reports by post to Chaengwattana IF it's postmarked at least 14 days before you mail it
Here's the address:
ATTENTION 90 Day Reporting
Immigration Office Division 1
Chalermprakiat Government Complex
120 Moo 3 Chaengwattana Road Soi 7
Thungsonghong, Laksi Bangkok
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