Seeing this in console

Failed to run a 5.00 timer in 'VendingManager v0.2.6' (NullReferenceException: Object reference not set to an instance of an object)   at Oxide.Plugins.VendingManager.SaveVendingMachineData () [0x00000] in <2697db18818747efbe239608e9330536>:0
    at Oxide.Plugins.VendingManager.SaveVMsAndLocks () [0x00081] in <2697db18818747efbe239608e9330536>:0
    at Oxide.Plugins.VendingManager.<OnServerSave>m__0 () [0x00000] in <2697db18818747efbe239608e9330536>:0
    at Oxide.Core.Libraries.Timer+TimerInstance.FireCallback () [0x00018] in <4452f821def6406d834e4149849fe7ea>:0

it seems it maybe related to economics in some way. I am not able to buy anything from machines with economics money (blood) it says I cannot afford.

If I have blood in my inventory I can purchase items. I am getting the folowing errors on console.

On plugin reload

> o.reload VendingManager
VendingManager was compiled successfully in 1831ms
Failed to call hook 'Unload' on plugin 'VendingManager v0.2.6'
(NullReferenceException: Object reference not set to an instance of an object)
at Oxide.Plugins.VendingManager.SaveVendingMachineData () [0x00000] in
<4d4e747004af497ba7618684172ff797>:0
at Oxide.Plugins.VendingManager.SaveVMsAndLocks () [0x00081] in
<4d4e747004af497ba7618684172ff797>:0
at Oxide.Plugins.VendingManager.Unload () [0x00017] in
<4d4e747004af497ba7618684172ff797>:0
at Oxide.Plugins.VendingManager.DirectCallHook (System.String name,
System.Object& ret, System.Object[] args) [0x00393] in
<4d4e747004af497ba7618684172ff797>:0
at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod
method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0
at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[]
args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0
at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[]
args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0
Unloaded plugin VendingManager v0.2.6 by ignignokt84
[VendingManager] Economics detected - money purchases enabled
[VendingManager] ServerRewards not detected - RP purchases disabled
Loaded plugin VendingManager v0.2.6 by ignignokt84

On server save I see this error in console

Failed to run a 5.00 timer in 'VendingManager v0.2.6' (NullReferenceException:
Object reference not set to an instance of an object)
at Oxide.Plugins.VendingManager.SaveVendingMachineData () [0x00000] in
<2697db18818747efbe239608e9330536>:0
at Oxide.Plugins.VendingManager.SaveVMsAndLocks () [0x00081] in
<2697db18818747efbe239608e9330536>:0
at Oxide.Plugins.VendingManager.<OnServerSave>m__0 () [0x00000] in
<2697db18818747efbe239608e9330536>:0
at Oxide.Core.Libraries.Timer+TimerInstance.FireCallback () [0x00018] in
<4452f821def6406d834e4149849fe7ea>:0

Those errors are related to your VendingMachine.json file under oxide/data, not Economics. The file is most likely corrupt.

Thanks wulf