Is it possible to cancel an extension of stay at Immigration? Here is some background information. May wife is Thai and also hold a Swedish citizenship, and when we moved permanently to Thailand two years ago she was forced to use her Swedish passport with a non-immigrant visa. She was applying for a new Thai passport (the old was expired) in Sweden but hence  to her name change after we were married, The Thai Embassy in Sweden couldn’t issue a new passport to her just because of the name change and they stated she had to start the name changing process at her local amphoe in Thailand to get a new Thai ID with correct name and after that get a new passport here. Now she has to go to Immigration every year and get a new extension for 1900 THB and they are saying as soon as she fly out with her Swedish passport it would get resolved and they suggest always to use her new Thai passport when she enter Thailand, I feel it very strange that they can’t do it in Thailand, and why should a Thai national have to deal with visa extensions and shell out 1900 THB every time.      

Is Anyone have this experience of a similar matter. 

What they say is exactly what they say to everyone. That is how it should be done. Just get her a trip out of Thailand on her Swedish passport and back on her Thai one. Quite a few dual nationality people have the same thing.

She indeed needs to exit by air using that passport and return using the Thai passport.  But she could have returned using expired Thai passport previously.  It is not a conciliation of extension of stay that is needed - that ends on exit - but she needs to exit on that other passport to clear immigration records.