Thai immigration give first "normal" 30d extension. After this can apply Covid 60d extension. In my case immigration (Bangkok) gave me 30d Covid stamp. Last day i went back and they give another 30d stamp.
I had almost the same situation than you. Then i entered again from Cambodia to Thailand. I got new visa exemption stamp as a usual. They said i will not get possible 30 day. extension and i should travel outside to apply tourist visa. But yesterday immigration provide extension me without any concerns. TIT 🙃