Sharp copier sf 2530

Question

technician serviced the copier & replaced developer &tonner. used code 42 sub code 01 to clear blinking developer light. this could clear. developer light (blinking) continued. making copy resulted in blank copy. later the machine gave false indicator that it is undertoned when code 25 was used. (no enogh tonrer available) yet tonner and developer was just replaced.

plse help clear the developer indicator having replaced new developer.
help sove blank copies

the copier was OK until the developer indicator came on