how to add net manually in PCB editor ???

You need an Allegro XL license (16.3 or older) or Allegro PCB Designer + High Speed option to do this. Then use the Logic - Net Logic command.

For anything less that the license make the change in the schematic and re-import the netlist or export a netlist from the PCB, edit and then re-import. There are many threads in this forum describing this process. 

 hi

thanks for reply 

but in my design have only 5 components, logic --->net logic after that create new net name like (N12373) and select the pin .net N12373 has not  assign for this component (i have not schematic ) (how to add net even i followed your procedure)

You need to do Logic - Part Logic first and create the parts, then you can use Logic - Net Logic to add nets to the parts. It's much quicker to draw a schematic and do it properly (IMHO).

Not sure wothout seeing your design but Logic - Net Logic, then Create - Enter net name and then LMB (left mouse button) the pin(s) (they will hilight) and the net is added. To add parts to existing nets click Logic - Net Logic then click on the netname then click on the pins you want to add.

Are there any error messages on the command line when you try to add the connections from C5 and C4 ? Are these parts added via the Part Logic function ?