NV Manager

I have VS985 on 24B. After rooting, I noticed that my IMEI number changed to 0. I tried to change it back to what it was (from IMEI on the box) using QPST NV_Manager, but for some reason when I try to write to nv item 550. I gives me an error, saying nv item is read only. Is there anyway to get write access to nv item 550? Thank you