Would appreciate any assistance in that for no reason at all my Mavic Pro no longer assess its position when taking off so it will not land automatically. Would appreciate any input and assistance. I am a novice flyer.

Are you giving it enough time to aquire gps lock? Does the rear light flash yellow , then goes to green when gps lock been achieved? This can take as long as 5/10 minutes on a brand new machine.
Are you in a clear area with clear visibility of the skies?

On the take off slider there is a small check box that you need to select for precision landing,  the AC then ascends to 6 m (I think) to orientate itself with the landing spot.

Is this what your referring to ?

When I first received my Mavic I noticed that as well. For the first few flights you had to give Mavic permission to land. I believe somewhere in settings you can change that but can’t remember where or if it stopped on it’s own.

Is it not able to record the Home Point? Have you checked the GPS signal via the APP? Make sure there are more than 10 satellites can be detected before you take off.
If not, you may need to be more specific for better assistance.