I guess the Embassy was correct. How do you think we can advice if we do not know how you applied?
If the nationality at birth does not match, the information given on the refugee travel document and the passport, you have to figure out how to get documents with matching data.
DTV is valid for 5 years and during this validity you get 180 days of stay when you enter Thailand
a Non Immigrant O visa gives once 90 days on entry, you are allowed to work with this visa in combination with the work permit, which can only applied for by a Thai company.
a Non Immigrant B visa only gives once 90 days on entry and can only be obtained in combination with a work permit, which can only applied for by a Thai company.
If you need to work on-line for a company outside Thailand, the DTV is the best option
The notification of stay is dated on the day you get registered at Immigration and that address stays the same until you move to another address which is reported OR when you leave the country,
The notification must be done within 24 hours of arrival.