can erase nrf51422 module but not able to program it

[The world peace]

i have an external nrf51422 module, and i can to erase it using nrfgo studio by nrf51 DK, but i can't program it with nrfgo studio , or by keil . and i can't open the program softdevice window in nrfgo studio. and all my connections are correct :

nRF52-DK Custom / External Board

VDD ------+-------------> VDD

VTG ----+-------> VDD

GND ------------------+-------> GND

GND DETECT ------+-------> GND

SWD IO -----------------> SWD IO

SWD CLK ----------------> SWD CLK

[The world peace]

i think i got the answer from you Jørgen Holmefjord, this is the oldest version on n51422, it's not intended and has the ability to re-program the softdvice, thank you Jørgen Holmefjord, and kangmin for your efforts.