@User Is there a way to make a reduction to the extraction poly res connected in series like transistors and also how to extract the resistance value also is there a method to change the letter of the extracted device

The issue here is that you are running from a tool that isn't magic, and magic reverts to the continous resistor model (res_xhigh_po) instead of the specific one (res_xhigh_po_0p35). Magic's device generator drops a special layer type on the device to denote the special extraction type. Since that special layer doesn't have a GDS layer associated with it, it gets lost between GDS write and read, and will not be present in a layout written by something other than magic.

Is this mean that if I used any layout tool other than magic magic won't extract it correctly ? I'm just asking

I need to check on the device type it is producing for the generic

xhigh_po

model. It might be wrong. The generic model should work in simulation.

Is there a way to reduce the resistors connected in series to one from magic

No. Magic does not do any series reduction, nor should it.