Arrow Samsung A520F Reading SN... error (1)

Operation: Unlock
Selected model: SM-A520F
Software version: 29.5

Searching Samsung modem... detected COM317
Reading phone info... OK
Model: SM-A520F
AP version: A520FXXUACSE6
CSC version: A520FVFRACSE7
CP version: A520FXXUACSE6
Product code: VOD
Phone SN: R58J310P2AY
Unique number: CBJ1042F5FC5C24
Reading IMEI... OK
IMEI: 3576610837*****
Reading SN... error (1)

Done with Samsung Tool PRO v.29.5