How to recover htc m7 wls imei

originallly phone had imei but with restarting issues so i flashed ruu and imei is lost

BEFORE:
C:\fastboot>fastboot getvar all
(bootloader) version: 0.5
(bootloader) version-bootloader: 1.60.0000
(bootloader) version-baseband: 1.00.31.0603
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 3.05.651.5
(bootloader) version-misc: PVT SHIP S-OFF
(bootloader) serialno: FA345S901877
(bootloader) imei: 355859056075567
(bootloader) meid: 99000146530807
(bootloader) product: m7_wls
(bootloader) platform: HBOOT-8064
(bootloader) modelid: PN0720000
(bootloader) cidnum: 11111111
(bootloader) battery-status: good
(bootloader) battery-voltage: 3819mV
(bootloader) partition-layout: Generic
(bootloader) security: off
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: dirty-91bb20e1
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0
all: Done!
finished. total time: 0.078s

AFTER flashing RUU_M7_WL_L50_SENSE60_SPCS_MR_Sprint_WWE_6.23.651. 10.exe

IMEI IS LOST

c:\fastboot>fastboot getvar all
(bootloader) version: 0.5
(bootloader) version-bootloader: 1.61.0000
(bootloader) version-baseband: 1.02.20.0922
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 6.23.651.10
(bootloader) version-misc: PVT SHIP S-OFF
(bootloader) serialno: FA345S901877
(bootloader) imei: 355859056075567
(bootloader) meid: 99000146530807
(bootloader) product: m7_wls
(bootloader) platform: HBOOT-8064
(bootloader) modelid: PN0720000
(bootloader) cidnum: 11111111
(bootloader) battery-status: good
(bootloader) battery-voltage: 3796mV
(bootloader) partition-layout: Generic
(bootloader) security: off
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: dirty-0e2a13e5
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0
all: Done!
finished. total time: 0.072s