I don't think it was out of the ordinary, since I've initially mentioned the situation to the officer when I had arrived, and he told me "no problem, just wait for the new visa, and then come back to us, we'll change it"
to be honest I was in a similar situation in Vietnam recently, and they were able to change it. I had applied for the 3 month tourist visa. I didn't arrive on time, so I've entered the country on a 30 day exemption. The next day the visa came, I printed it out, went to the airport, an in 20 they've changed my stamp. So that's why I had high hopes and asking here for potential workarounds
So I know certain visas can be exchanged inside Thailand, but since I don't have an actual visa but rather an exempt stamp, then that cannot be changed, is that correct?