Item prototypes

[Gsmith]

Hello,
I'm looking for some help on my Item prototype.
Currently I'm monitoring a Cisco Switch 3750 in my lab environment.
Using Zabbix Server 3.0.1, Zabbix Proxy server 3.0.1 on CentOS 7.
I ran snmpwalk as shown below;
root# snmpwalk -v 2c -c public 10.200.6.16 CISCO-VTP-MIB::vtpVlanTypeExt

The output;
CISCO-VTP-MIB::vtpVlanTypeExt.1.1 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.101 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.102 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.105 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.111 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.112 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.113 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.114 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.115 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.121 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.122 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.123 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.1002 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.1003 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.1004 = BITS: 80 vtpmanageable(0)
CISCO-VTP-MIB::vtpVlanTypeExt.1.1005 = BITS: 80 vtpmanageable(0)


I executed snmptranslate as shown below;
root# snmptranslate -Td CISCO-VTP-MIB::vtpVlanTypeExt

The output;
CISCO-VTP-MIB::vtpVlanTypeExt
vtpVlanTypeExt OBJECT-TYPE
-- FROM CISCO-VTP-MIB
-- TEXTUAL CONVENTION VlanTypeExt
SYNTAX BITS {vtpmanageable(0), internal(1), reserved(2), rspan(3), dynamicGvrp(4)}
MAX-ACCESS read-only
STATUS current
DESCRIPTION "The additional type information of this VLAN."
::= { iso(1) org(3) dod(6) internet(1) private(4) enterprises(1) cisco(9) ciscoMgmt(9) ciscoVtpMIB(46) vtpMIBObjects(1) vlanInfo(3) vtpVlanTable(1) vtpVlanEntry(1) vtpVlanTypeExt(17) }


I created Item prototype as followed;

NAME={#SNMPVALUE} Type Ext
TYPE = SNMPv2 agent
KEY = snmp.agent[CISCO-VTP-MIB::vtpVlanTypeExt.{#SNMPINDEX}]
SNMP OID = CISCO-VTP-MIB::vtpVlanTypeExt.{#SNMPINDEX}
SNMP community = {$SNMP_COMMUNITY} (i.e. public)
Type of information = Character
Show VALUE =Vlan Type Ext (value map)

My Value map for Vlan Type Ext consist of the following;

NAME = Vlan Type Ext
MAPPINGS ={vtpmanageable(0), internal(1), reserved(2), rspan(3), dynamicGvrp(4)

I'm not receiving data and whats odd is in latest data in column LAST VALUE show a "?" as show below;
EXAMPLE:

AD Type Ext
snmp.agent[CISCO-VTP-MIB::vtpVlanTypeExt.1.111] 60 90 SNMPv2 agent 2016-05-12 00:04:30 ?

IF I change value Type of information on the Item prototype I get unsupported OID.
I confused why it discovers all my VLANS and names them but dos not show the required data.
any help would be appreciated. Thanks