Minor issue at FMC

Planning a flight at ground, I found a minor issue regarding step climb.In CLB page there is a speed restriction usualy 250/10000, but when by any reason I program a step climb in CRZ page that restriction just disapears and no way to put it back again in scratchpad and line select it back. The same happens in DES page with 240/10000 it disapears. Everything goes back to normal when I delete the step Climb. Im Just reporting that minor issue, and my appologies if that wasnt an issue, I did not have time to read all manuals yet. Regards,Alexandre