Automatic colocation change

I'm connected to Frankfurt (FRA) for over 2 months for fast and secure internet until today when my internet speed dropped under 50 mbit/s. until I check ROBLOX (I'm developer on that platform) and it blocked access and, I thought internet speed was extremely low so I check speed and it appeared under 50 so, I check colocation center and it appeared IST (Istanbul) and I didn't check settings since first successful connection. (lowest before change was over 50 mbit/s and maximum was 300 mbit/s)