Netgear nighthawk AC1750 R6700v3 not wanting to take gigabit speed

So I recently upgraded to gigabit speed internet via fiber, and noticed my internet speed was not increased. after several hours of talking with my ISP service provider we have determined it must be the router. I plugged my computer directly into the modem and was registering 1000 speed. but when plugged into the router im stuck at 100. ive tried to look through all the settings in the router login control panel and couldnt find anything pertaining to this. I read something about a connection aggreation setting or something but it seems like that was for a different router, and when trying to look for this setting under my control panel I could not find anything. really hoping someone can help me figure this out