@Timothy ******
the Phuket immigration office told I couldn't. The reason is that I was on a 90 day marriage visa and they no longer accepted our US marriage certificate, so I couldn't get an extension of permission to stay in the Kingdom. If you are on a marriage extension of permission to stay in the kingdom, you can change in the country the reason for extension, but I wasn't allowed to change from non Immigrant 90 O marriage to a non immigrant O based on retirement. It didn't make a lot of sense to me, but you just have jump through the hoops and the hoops keep changing. I've been dealing with Phuket Immigration since 2006. It used to be a lot easier.