Hambam does this (same breed and colouring). Only for the first hour of me rocking up to look after it. I crouch down, he walks up and does the exact same thing for a few mins each time.

I’ve always put it down to something related to seperation anxiety, or just a weird greeting or both.

Poor doggo coming from a puppy farm though. That breed needs a shitload of attention or things can go south mentally.