In am assembly, constraints don't work

I attached the file.

Even though i placed constraints on the sheet metal part, it still moves and rotates

Beam.zip

I don't see any parts?

An assembly without parts is useless.

When i press update, the sheet metal part takes it's right place, but i can move it

Beam.zip

Are you using the Move command or are you clicking and dragging on the part to try to move it?

The Move command temporarily overrides all assembly constraints to allow you to temporarily move a part out of the way.

That is what the Move and Rotate commands are supposed to do - Move or Rotate.

Also, I noticed that your sketches are still not constrained and that you are doing too much work.

You should (almost) never repeat dimensions. Add geometry constraints like equal(=) rather than double dimensions.

You were also missing tangent constraints.