Garageband: Space bar is not working for play and pause

Space bar worked very well before, but suddenly it is not. When I press space bar repeatedly, the mouse cursor appears at a certain fixed position and it clicks the position. I don't know why. It's 16" macbook pro and it's quite new, only one month old and the OS has been updated to the latest version. By the way, the space bar works very well for other apps as you can see this question (I'm writing this with the macbook pro).

Please help me. Thank you.