GuildGui1b

Error while running the chunk
  [string "Mods/Addons/GuildGui1b/Scripts/ScriptGuildGui1b.lua"]:1158: attempt to index local 'joinTimeMin' (a nil value)
  func: __index, metamethod, line: -1, defined: C, line: -1, [C]
    func: NormalizeJoinDate, global, line: 1158, defined: Lua, line: 1150, [string "Mods/Addons/GuildGui1b/Scripts/ScriptGuildGui1b.lua"]
      func: CreateBase, global, line: 254, defined: Lua, line: 234, [string "Mods/Addons/GuildGui1b/Scripts/ScriptGuildGui1b.lua"]
        func: ?, ?, line: 1024, defined: Lua, line: 981, [string "Mods/Addons/GuildGui1b/Scripts/ScriptGuildGui1b.lua"]