I always do and I’m always doing
I always do (something) = I do it every time
“I always ride my bike to work.” = every time I go to work I go by bicycle
I’m always doing (something) = I do something very often, more often than usual or too often. This has more of a negative meaning.
“I can’t find my car keys! I’m always losing things.” = I lose things very often, I lose things too much!
“In the spring time it often rains suddenly so I always carry a small umbrella when I go out.”
“Jim is always sleeping on the couch, it’s not good for his back!”
“You are never happy with anything. You’re always complaining.”