Same for me, I test my game and it is English only but others tell me they hear portuguese AND english, just like I heard on yours. I have no idea! I'll give yours another shot soon.
I’ve just updated my game again and added "en-US" to the language for the Speech Synthesis in Construct 3 — I had previously left it as default. There isn’t much documentation on this feature, so I hope this fixes the issue. I can’t really test it myself.
By the way, I played your game recently and really enjoyed it! It’s very well made, and the concept is brilliant. I noticed it played in English only, and worked perfectly. I especially liked how the choices reveal more about yourself, like your patience level, and the ending felt very satisfying.
One minor suggestion: when I picked an option, it would continue reading the other options. I understand you’re meant to listen to them all, but maybe there’s a way to make it so it continues.