[Makita Cordless 10" miter stuck in bevel position]

Mine won't lock on zero on bevel since I've had it have to hand tighten and always is moving! Used someone else's and it locked don't know what to do....

[Cordless skillsaw]

Thanks it's brushless though

 

[Cordless skillsaw]

My 6 1/2 cordless skillsaw won't start when trigger is pulled. Spin blade and try again it starts. Over and over what is wrong with it??