我支付了150美元的UPS运输费用,其中包括10美元的保险和20美元的包装费用,但我看到贵公司所采用的是普通的邮政运输且

I paid USD150 for UPS delivery of the parcel including USD10 fr insurance and USD20 for packing. But I found the parcel was delivered by general post transport which is USD30 only and without insurance. Could ask for refund of the paid amount less the post charge (USD30) and packing charge (USD20)?