very poor services for courier services

if i could rate 0 i would. i have been doing business with them for a few years now. unfortunately we are in a small town so its the only courier services that we as a business can really use. but i always have problems with this guys. as a business i always try my best to guarantee my clients the best fastest services but with this company its just not possible. if they don't loss my packages, they take days before crediting my account. really disappointed.