Retrieving data from SNMP probe variables - security

Question

When SNMP walking or using a 'Single OID Viewer' probe I can retrieve any of the OIDs information. However, when trying to use the custom probe from the interactive snmp probe creator all of the OIDs return '[N/A]'
Any help would be greatly appreciated.
I am adding more info below for context
1. snippet code for a custom probe
2. what I am expecting
3. What my code returns
Below is an example code for the OID variables I require
-- The purpose of the code is to record status data from a device and displays the device status for user.
<snmp-device-variables>
TLPPOIName_, spvLDasName.${Slot},DEFAULT, "TLPPOIName"
PoiDescription_, spvLDasCommercialDescription.${Slot},DEFAULT, "PoiDescription"
PoiAttDl1_, spvLDasAttDigDl.${Slot}.1,DEFAULT, "Poi Attenuation Dl path 1"
PoiAttDl2_, spvLDasAttDigDl.${Slot}.2,DEFAULT, "Poi Attenuation Dl path 2"
PeakPwr1_, spvLDasPeakPwrDl.${slot}.1, DEFAULT, "PeakPwr path 1"
PeakPwr2_, spvLDasPeakPwrDl.${slot}.2, DEFAULT, "PeakPwr path 2"
PwrAlarm_, spvLDasPwrAlarmHysteresis.${Slot},DEFAULT, "PwrAlarm"
</snmp-device-variables>`
<datasets>
$PoiAttDl1_, "PoiAttDl1", "dB", "true", "Poi Attenuation Dl path 1"
$PoiAttDl2_, "PoiAttDl2", "dB", "true", "Poi Attenuation Dl path 2"
$PeakPwr1_, "PeakPwr1", "dBm", "true", "PeakPwr path 1"
$PeakPwr2_, "PeakPwr2", "dBm", "true", "PeakPwr path 2"
$PwrAlarm_, "PwrAlarm", "dBm", "true", "PwrAlarm"
</datasets>`
<snmp-device-display>
\B5\TLPPOI\P0\
\4\ TLPPOIName:\0\ $TLPPOIName_\M0\
\4\ PoiDescription:\0\$PoiDescription_ \M0\
\4\ Poi Attenuation Dl path 1:\0\$PoiAttDl1_ \M0\
\4\ Poi Attenuation Dl path 2:\0\$PoiAttDl2_ \M0\
\4\ PeakPwr path 1:\0\$PeakPwr1_ \M0\
\4\ PeakPwr path 2:\0\$PeakPwr2_ \M0\
\4\ PwrAlarm:\0\$PwrAlarm_\M0\
</snmp-device-display>
SNMP walk results: Below are example of values I expect to see
VZW 800
20
2
Display window after I use the custom probe I wrote
TLPPOIName: [N/A]