Most likely you are in 3D mode and drawing 2D, try to change that down on Inspector bar >> Toggle 2D/3D, you can also open the Selector Property and set it to 2D/3D depending …….
To fix it, turn of 3D Objects if you have, select everything left (2D) with ctrl + a, then set workplane by World (or where you want it) (ctrl+alt+w) and then Place on workplane (alt+shift+w) and it should been done
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