When DD was in grade 2 we encountered some unwilling teachers. I arranged a meeting and they looked at the 15 page psych-ed assessment, put it on the desk and told me "we don't see it" and then said that "she doesn't need anything special".

I then proceeded to outline the behaviour we were seeing at home that coincided with the start of that school year - crying every day, resisting going to school, lashing out at us and her brother, etc. She had completely changed personalities and it was only getting worse. I emphasized that this was the reason I was looking for advanced work. This is what she was begging for at home and the lack thereof was at the root of her angry outbursts at home. They might not see that she "needed" it but we did.

The teachers looked stunned and eventually agreed to our request. Distancing myself (as a "pushy parent") from the whole thing was key. This wasn't about me, this was about DD and her needs and that is all.

In DS's case the only way we convinced unwilling teachers was that he was a royal PITA when not engaged. We eventually managed to convince them that it would likely make their lives easier if they made a teeny tiny bit of effort to give him some enrichment. Once they saw that it worked they were more likely to put in the extra effort to keep him occupied.

I'll also second/third? the opinion above to see if you can get moved. Advocating 15 minutes every single year to be matched with the teacher that was most willing/capable of providing gifted differentiation was the most productive advocacy I ever did.