Even with an agent the agent completed the paperwork but you give him all the documents and they send you outside of Thailand to apply. You pay accom and travel. It must be an embassy outside of Thailand. You may be called for an interview at that embassy. So you must attend. You just don't want to admit your wrong. Why don't you say who can do it inside Thailand let everyone know so they can go there and get dtv
Your best to ask the clinic not here. Are they registered ,can they do paperwork for you. Don't ask here most don't know. I haven't seen anyone apply like this. Not same as Muay Thai they are registered
Are you for real ?? You think you are the first to get a new passport with long-term visa or stamp. Your DTV is an email so you have it electronic. Your stamp is for 180 days take your old passport if you want. Immigration has electronic record you think the only record is your stamp please this has been discussed here 1000 times. You are so naive about your visa and passport it's your responsibility to know before you get to this point. Don't be lazy