Prize difference

Contacted company for prizing on 3kg plastic bags. they gave me an prize. And two of there branches give me the same prize. (Driving round trip 320 km ) on arriving at company the prize was totally different by R1200 more than spoken on phone not 2 hrs earlier. Asking the same prize as 20km from home. They did not want to give the bags at the price it was told on phone. This is very bad as i lost alot of money due to incorrect info from them (2 branches told the same prize and can not hold there word. )