I have heard of issues with Alexa/Echo and Hue, mainly caused by the setup in each app being inconsistent. If you ever have issues finding your bridge (but were able to connect to it previously), that’s likely the reason. Disconnect it as a device under the Alexa/Echo app and restart with just the Hue.
I’m a Hue fanatic. I got a few color ones and a bridge thrown in for fun when I bought a TV at best buy - I loved them so much (and love them for seasonal decorations especially) that I ended up buying 33 more (all color - make sure you buy the latest versions (3rd E) as the earlier versions have issues with Green colors being less dark, but otherwise are identical), including a couple of lightstrips, GU-10s for my spot lighting, etc., replacing all the lights in my house. I mainly control them through Google home these days, and have managed to get a few of my friends to jump onboard with Hue after seeing the effect they can have.