How to combine disconnected line

I made rectangle with line and disconnected it. now 4 seperated lines and I want to reconnect each line as a one rectangle . how to do this?? there is no option join or combine, reconnect.??


You can lock points at each corner.

You can also move slightly each point at each corner and put it back to its original location. It will reconnect the line to its neighbour.


thank you it works !