14x AddOnSkins/Core/Core.lua:280: attempt to call upvalue 'IsAddOnLoaded' (a nil value)
[string "@AddOnSkins/Core/Core.lua"]:280: in function ?' [string "@ElvUI_Libraries/Core/CallbackHandler-1.0-8/CallbackHandler-1.0.lua"]:109: in function <...ies/Core/CallbackHandler-1.0/CallbackHandler-1.0.lua:109> [string "=[C]"]: ? [string "@ElvUI_Libraries/Core/CallbackHandler-1.0-8/CallbackHandler-1.0.lua"]:19: in function <...ies/Core/CallbackHandler-1.0/CallbackHandler-1.0.lua:15> [string "@ElvUI_Libraries/Core/CallbackHandler-1.0-8/CallbackHandler-1.0.lua"]:54: in function Fire'
[string "@ElvUI_Libraries/Core/Ace3/AceEvent-3.0-4/AceEvent-3.0.lua"]:120: in function <...UI_Libraries/Core/Ace3/AceEvent-3.0/AceEvent-3.0.lua:119>

Locals:
self =

{
FrameLocks = {
}
modules = {
}
Skins = {
}
SkinErrors = {
}
hooks = {
}
Version = 4.680000
EmbedSystem = {
}
name = "AddOnSkins"
preload = {
}
skins = {
}
MyName = "Sharipriest"
MyRealm = "Blackhand"
defaultModuleState = true
Authors = "Azilroka Nihilistzsche"
ProperVersion = "4.68"
enabledState = true
Wrath = false
Retail = true
baseName = "AddOnSkins"
Options = {
}
defaultModuleLibraries = {
}
AddOnVersion = {
}
TexCoords = {
}
AddOns = {
}
Faction = "Alliance"
Libs = {
}
orderedModules = {
}
Classic = false
Title = "|cff16C3F2AddOn|r|cFFFFFFFFSkins|r"
MyClass = "PRIEST"
TicketTracker = "https://github.com/Azilroka/AddOnSkins/issues"
events = {
}
TBC = false
}
event = "ADDON_LOADED"
addon = "AddOnSkins"
(*temporary) = nil
(*temporary) = "AddOnSkins"
(*temporary) = "attempt to call upvalue 'IsAddOnLoaded' (a nil value)"
AS = {
FrameLocks = {
}
modules = {
}
Skins = {
}
SkinErrors = {
}
hooks = {
}
Version = 4.680000
EmbedSystem = {
}
name = "AddOnSkins"
preload = {
}
skins = {
}
MyName = "Sharipriest"
MyRealm = "Blackhand"
defaultModuleState = true
Authors = "Azilroka Nihilistzsche"
ProperVersion = "4.68"
enabledState = true
Wrath = false
Retail = true
baseName = "AddOnSkins"
Options = {
}
defaultModuleLibraries = {
}
AddOnVersion = {
}
TexCoords = {
}
AddOns = {
}
Faction = "Alliance"
Libs = {
}
orderedModules = {
}
Classic = false
Title = "|cff16C3F2AddOn|r|cFFFFFFFFSkins|r"
MyClass = "PRIEST"
TicketTracker = "https://github.com/Azilroka/AddOnSkins/issues"
events = {
}
TBC = false
}
IsAddOnLoaded = nil
AddOnName = "AddOnSkins"

[12:42:28] 222x AddOnSkins/Core/Core.lua:266: attempt to call upvalue 'IsAddOnLoaded' (a nil value)
[string "@AddOnSkins/Core/Core.lua"]:266: in function ?' [string "@SharedMedia/libs/CallbackHandler-1.0-8/CallbackHandler-1.0.lua"]:109: in function <...dia/libs/CallbackHandler-1.0/CallbackHandler-1.0.lua:109> [string "=[C]"]: ? [string "@SharedMedia/libs/CallbackHandler-1.0-8/CallbackHandler-1.0.lua"]:19: in function <...dia/libs/CallbackHandler-1.0/CallbackHandler-1.0.lua:15> [string "@SharedMedia/libs/CallbackHandler-1.0-8/CallbackHandler-1.0.lua"]:54: in function Fire'
[string "@ElvUI_Libraries/Core/Ace3/AceEvent-3.0-4/AceEvent-3.0.lua"]:120: in function <...UI_Libraries/Core/Ace3/AceEvent-3.0/AceEvent-3.0.lua:119>

Locals:
self =

{
FrameLocks = {
}
modules = {
}
Skins = {
}
SkinErrors = {
}
hooks = {
}
Version = 4.710000
EmbedSystem = {
}
name = "AddOnSkins"
preload = {
}
skins = {
}
MyName = "Sintvoker"
MyRealm = "Argent Dawn"
defaultModuleState = true
Authors = "Azilroka Nihilistzsche"
ProperVersion = "4.71"
enabledState = true
Title = "|cff16C3F2AddOn|r|cFFFFFFFFSkins|r"
baseName = "AddOnSkins"
Options = {
}
defaultModuleLibraries = {
}
AddOnVersion = {
}
TicketTracker = "https://github.com/Azilroka/AddOnSkins/issues"
AddOns = {
}
Libs = {
}
orderedModules = {
}
Hider = Frame {
}
Classic = false
TexCoords = {
}
MyClass = "EVOKER"
Wrath = false
Retail = true
Faction = "Alliance"
events = {
}
TBC = false
}
event = "ADDON_LOADED"
addon = "AddOnSkins"
(*temporary) = nil
(*temporary) = "AddOnSkins"
(*temporary) = "attempt to call upvalue 'IsAddOnLoaded' (a nil value)"
AS = {
FrameLocks = {
}
modules = {
}
Skins = {
}
SkinErrors = {
}
hooks = {
}
Version = 4.710000
EmbedSystem = {
}
name = "AddOnSkins"
preload = {
}
skins = {
}
MyName = "Sintvoker"
MyRealm = "Argent Dawn"
defaultModuleState = true
Authors = "Azilroka Nihilistzsche"
ProperVersion = "4.71"
enabledState = true
Title = "|cff16C3F2AddOn|r|cFFFFFFFFSkins|r"
baseName = "AddOnSkins"
Options = {
}
defaultModuleLibraries = {
}
AddOnVersion = {
}
TicketTracker = "https://github.com/Azilroka/AddOnSkins/issues"
AddOns = {
}
Libs = {
}
orderedModules = {
}
Hider = Frame {
}
Classic = false
TexCoords = {
}
MyClass = "EVOKER"
Wrath = false
Retail = true
Faction = "Alliance"
events = {
}
TBC = false
}
IsAddOnLoaded = nil
AddOnName = "AddOnSkins"

Also getting the same error