Hi,
Respected sir,
I am having error in assigning material in edit mode.
step to find it.

1. create any model or choose any.
2. assign a material to it.
3. create any other material by clicking on the + button at the right side of material list in properties panel.
4. select your model, choose any face or ngon.

you will notice an error in geometry of model, it will get removed after removing material.
Thanking you
Bhavesh
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