Which mirrors do you have?
The lozenge shaped mirrors often supplied from new are very difficult to adjust to give an adequate view. I changed mine to round door mirrors from Librands. These are relatively easy to adjust to give a good field of view.

Paul
Costock, UK
2014 4/4 Rolls Royce Garnet Red
Disco 5
Teddy - 17h1 Irish Draught cross