Either it takes some time or it is impossible to use snap points like end point or mid point in 2D drawings.
Options Cache 2D Display is not activated in the Global Settings/Options.
Cache 2D Display: The result of all line calculations effected by the volume modeler (e.g. at a 2D-depiction, object snap, etc.) is written into an intermediate storage. A new calculation is only made in case of modifications. Thus the processing speed for the determination of AutoCAD® - object snap-points especially in case of complex construction groups is considerably increased.
1. Open the Global Settings or Options by holding the right mouse button in the View window and then click on the Options.
2. Left click on the Display tab and activate the option Cache 2D Display this will uses cache for display of 2D elements which will speeds up object snap calculation.
3. Reopen 2D drawing and now it's easy to snap the points.