Selection of make etc on cars for sale form

[928Elan]

I used to be able to use the cars for sale pages with my Nokia Windowsphone. However, it's been increasingly difficult since around Christmas 2016. I now find it almost impossible to select a make - or indeed complete any fields apart from my postcode, which works differently of course. Has Pistonheads made a subtle change or was I just lucky in 2016? More to the point, can anyone offer a solution?