Not getting valid GPS location, only getting empty NMEA strings on /dev/ttyAMA0

Issue:Not getting valid GPS location, only getting empty NMEA strings on /dev/ttyAMA0

Setup: https://store.rakwireless.com/products/rak-discover-kit-2?variant=39945702473926

Server:
Raspberry Pi 4 Model B Rev 1.2
Rak2287 + Pi_Hat
OS - Ubuntu 20.04.4 LTS

Details:

  1. Installed the Pi OS 64 bit lite image http://downloads.raspberrypi.org/raspios_lite_arm64/images/ on a 16GB flash card.
  2. Ran raspi-config to enable\disable the following:
  • Select Interfacing Options
    • Select SPI
    • Select Yes
  • Select Interfacing Options
    • Select IC2
    • Select Yes
  • Select Interfacing Options
    • Select Serial Communictioans
    • Select No for shell access
    • Select Yes for serial port hardware
    • Select Yes to confirm
  • Save changes and reboot by selecting Finish
    • https://github.com/RAKWireless/rak_common_for_gateway
    • go to rak_gateway directory then installed install.sh script.
    • while installing selected 7 number option (7.RAK7248 no LTE (RAK2287 SPI + raspberry pi))
    • after installation ran ‘sudo gateway-config’
      - select ‘setup rak gateway lora concentrator’
      - select ‘Network is chirpstack’
      - select ‘select channel plan’
      - select ‘IN 865 - 867’
      - select ‘server ip’ - ok
      - select ‘chirpstack ADR configuration’
      - select ‘Enable ADR’

on rak_terminal run ‘cat /dev/ttyAMA0’
output: empty NMEA strings

[email protected]:~ $ cat /dev/ttyAMA0
7A
�b Xg�����$GNRMC,N2E
$GNGGA,GNGSA,A,1,99SA,A,1,99.991,1,00
79
$GLGSV,1,1,00
�b @k$GNRMC,0,00,99.99,GNGSA,A,992E
1,1,007V,1,1,0099,99.992E
�b (o�����$GNRMC,N2E
$GNGGA,9.99,GNGSA,A,9,99.99
2E
$GNGSA,A,1,9.992E
$GPGSV,1,1,00
7GLL,V,N7A
V,1,1,00
65,00,99.99,99.99,99.99,99.99*,99.99,99.99,99.992E
$GNGLL,v������$GNRMC,N
2E
$GNGGA,GNGSA,A,99.99,99.99,99.992E
$GNGSA,A,1,99.99,99.99,99.99
2E
$GPGSV,1,1,007V,1,1,0065
$GNGLL,V,N7A
,N
2E,N4D
1,1,00
7GLL,V,N7A,GNGSA,A,999,99.99SA,A,1,99.999.992E
1,1,00
7V,1,1,00GLL,999,99.99SA,A,1,99.999.992E
�b ��$GNRMC,N4D
$GNVTG,N
2E
$GNGGA,9.99,GNGSA,A,999,99.99SA,A,1,99.999.992E
$GPGSV,1,1,0079
$GLGSV,1,1,00GLL,V,N
7A
�b ��,N4D
$GNVTG,9.99,56
$GNGSA,A,9,99.99
2E
$GNGSA,A,1,9.99
2E
$GPGSV,1,1,007V,1,1,0065
$GNGLL,V,N7A
$GNRMC,V,N
4D
$GNVTG,NGGA,0,00,99.99,56
$GNGSA,A,99.99,99.99,99.99
2E
$GNGSA,A,1,99.99,99.99,99.992E
$GPGSV,1,1,00
7V,1,1,0065
$GNGLL,V,N
7A
1,1,0079,0,00,99.99,GNGSA,A,1,99.99,99.99,99.99SA,A,1,99.99,99.99,99.992E
$GLGSV,1,1,00
65
$GNGLL,
N2E�����=$GNRMC,N4D
$GNGGA,9.99,GNGSA,A,999,99.99SA,A,1,99.99
$GPGSV,1,1,00
79
$GLGSV,1,1,00GLL,
,NGGA,9.99,GNGSA,A,.99,99.99,99.99SA,A,1,99.991,1,0079
$GLGSV,1,1,00
�b ������$GNRMC,N2E
$GNGGA,GNGSA,A,1,99SA,A,1,99.991,1,00
79
$GLGSV,1,1,00GLL,�����H$GNRMC,N2E
$GNGGA,GNGSA,A,1,99SA,A,1,99.991,1,00
79
$GLGSV,1,1,00
�b �������$GNRMC,N*4D

problem: GPS coordinates are incorrect only getting empty nmea strings.