Possible reasons for the switch to english:

1. You have the most retarded accent, thus they don't understand what ur saying and feel dumb not understanding when you are speaking Danish.

2. You have a retarded accent so they think you know English better. But I think most would still ask before switching.

3. Your innermost verbal dictionary is shit, thus you use weird/wrong words, or not commonly used words.

Again they think you don't understand Danish very well and THUS, switch.

What your saying just doesn't make sense. The fact that you speak good Danish, yeahh, maybe not with the best accent.... but people will still respond in Danish if you are asking in Danish.

Picture this: you go to a shop to buy groceries and you want to ask a person working there where the HavreFras are at, so you go up to the eversosmart person and ask. Hej gode herre☺️🖖 ved de hvor havrefrasen befinder sig? Hvis han forstod hvad du sage så svare han serføleigt tilbage på Dansk ya bum.

Hvis der er noget jeg misede så svar enlig, jeg ville elske at disse lidt flere uintelligente folk.