Nokia

i just got this phone, pretty cool except for the backlight turning off way too quick. 🤨 from what i have read there is not way of adjusting this feature, the preset is 15 secs. they set this to save battery life. i guess my ? is, is that true can not be adjusted?, if not, i purchased my phone thru radioshack, would i return it there or do i call att? any help is appreciated..