Hi,
I have the same problem but my snmpwalk was ok.
snmpwalk -v2c -c mysnmp x.x.x.x
SNMPv2-MIB::sysDescr.0 = STRING: Cisco IOS Software [Fuji], ASR920 Software (PPC_LINUX_IOSD-UNIVERSALK9_NPE-M), Version 16.9.5f, RELEASE SOFTWARE (fc2)
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Compiled Fri 28-Feb-20 08:00 by mc
SNMPv2-MIB::sysObjectID.0 = OID: SNMPv2-SMI::enterprises.9.1.2102
DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (3629598652) 420 days,