print from iphone to HP 2600

I have been sending prints to my HP2600 series printer without any problem until recent. All of a sudden my iphone stopped showing colour option of the printer. Now I cannot take colour print from my phone. Problem remains same in anorher 2 iphones and ipad at home. Macbook works well for both colour and black prints. HP customer service did all they can do and printer has no problem of colour printing, but iphones don't show me the option to choose colour print. It doesnt set to default setting either. Please help me to solve this as this has made me two weeks of income loss. HP tried all possible ways, but no luck. They asked me to contact apple. Thank you