Switched my wifi to TP-Link 3 Deco mesh system and discovered random connection switching of my devices  to different Deco in the 1 story home. This may contribute to the behavior you observe. I took the path of assigning devices that are stationary to the respective Deco device and disabled the automatic optimization for those.

How can I take move some lights from 1 area to another...eg from main room ro living room

just unplug the dot if you do not want to use it anymore.   The show can handle most things.   However, it's been my experience the show does not hear as well as the dot so if all you need it for is to operate the lights, it won't make a difference which one did it.    I have two echo devices in the living room and for me, so not matter where I am in the room or what direction I am facing, the command I give will be heard.   

How can I eliminate the use of my echo dot and just use my echo show 5 3rd gen to operate my lights

When I first purchased my echo's, all was fine and working perfectly well. I could ask for a certain song and they would play it, no problem.

Now in the last few months, if I as for a certain song, it tells me it can only play specific songs if I sign up and pay for Amazon Music Unlimited. I Already pay a subscription to Amazon, why do I have to pay more now when everything worked perfectly well before!!!?

I'm sure this is called EXTORTION in legal terms, and Amazon should be ashamed of itself, they're already one of the wealthiest companies in the world, why would they need more money?