I think you need to contact the thai embassy in germany as i think you need their approval too. They can tell you where they will approve a health certificate from.
They said that no flights going out of the country so only by boat, which was 2 months and up. DHL is the only intl mail working now and its 0.5 kgs min even if you send lighter mail. Cannot send paper masks or any filters. They will check your package. Only reusable masks ok.
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