Bukkit

What is the issue?

I have a server with a world as prison using this plugin, but the mines desappear every time the server get restarted. All was fine and working during since i config the mines until the time i restart the server:

Please provide any additional information below.

I use:

- Spigot 1.7.5
- PrisonMine v.1.32    Release    Semi-normal    Jun 21, 2013    CB 1.5.2-R1.0     PrisonMine.jar    25,441
- Multiverse Core
- Multiverse money inv
- MultiInv
- essentials economy system
- Vault
- World Guard protection to cover all my prison
- WG (World Guard) to allow players to break and remove.

18.04 16:17:33 [Server] ERROR mineObj A was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj D was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj B1 was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj C was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj B was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj C1 was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj A1 was not found, but its TimeTrigger still exists
18.04 16:17:33 [Server] ERROR mineObj D1 was not found, but its TimeTrigger still exists

Greetings, Kate