i have been using a cheap glass cleaner on the windscreen but i have now noticed that it is making what look like scratch marks on the windscreen, but after a closer look they are not scratches but what look like residue left behind which can be wiped off.
has anyone got any preferences into what glass cleaner should be used??

THe best cleaner I used on my windscreen was a mixture of water, white vinegar and a couple of drops of washing up liquid. Also, newspaper is good for that final drying, or even a microfibre cloth (they're pretty good)

Try getting a clean microfiber and buffing off again.....

what product are you using? Many domestic glass cleaners contain silicone which make your windows look nice and shiny but leaves a residue

My go to favourite (especially as i got 4 ltrs of the stuff stockpiled when it was on offer) is Autoglym Fast glass


used sparingly put on and worked in well with one cloth leave to dry then buff up with a clean dry Microfibre

Autoglym fast glass is the bees knees, very easy to wipe off and get a smear
free shine.

If the glass isn't in new condition then maybe some autoglym glass polish. Monthly with the polish and weeks in between with fast glass?

It's also suitable for plastic "glass" (doesn't eat it) so did an excellent job on my parent's caravan last year As you can use it on plastic glass, it's excellent in the cabin on the radio, dials, and climate control display screen covers.