hello all, whenever i reopen the design in magic these cell pmos_3p3_KG2LTV doesn't expand. All other cell expand except these, where ever they appear. They are pmos with 2 finger of 0.5u each.

Likely you failed to save the parameterized cell after generating it. If there is no file

pmos_3p3_KG2LTV.mag

in the working directory of the layout, then that's probably what happened. You can use the device generator (menu

Devices 1 --> pmos

) to re-create it. It is just a 3.3V pFET, although from the size of the bounding box in the layout it looks like the guard ring may have been deselected. Note that the six-character suffix is a hash created from the device parameters; but it's a one-way hash, so you cannot recover the device parameters from the hash code. But you know what the width and length of the devices are, so you should be able to quickly find the set (or a set) of parameters that matches what was supposed to be in the layout.