Nissan Motors — Yellow warning light on screen

Address:

48A Calle Asturias, Cuidad Quesada , Rojales , Alicante

We as a company use Nissan in Torrevieja, we have a delivery van NV200 ( 5899 KDF) it has been in their garage seven times sometimes over the last six months, sometime for a week at a time, to resolve a yellow warning light that keeps coming on, the van is supplied by Sabadell renting and 'im sure you have charged them each time for resolving the problem?? now they will not answer my emails to them, Claire Young is the lady we deal with as she is English, this is an urgent issue and needs dealing with what can we do .