LibAlchemy error LUA

[gimmy77]

Hi guys, i receive this error many times, for example when i view my inventory or random. Any idea? Thanks.

user:/AddOns/LibAlchemy/LibAlchemy.lua:172: operator + is not supported for number + nil
stack traceback:
user:/AddOns/LibAlchemy/LibAlchemy.lua:172: in function 'LibAlchemy:getCraftingCost'
|caaaaaa<Locals> self = [table:1]{}, reagentsTable = [table:2]{1 = 150670}, itemLink = "|H0:item:76827:30:3:0:0:0:0:0:...", mainID = 76827, solvent = 3, CP = 27, result = -nan(ind), type = 2 </Locals>|r
user:/AddOns/AlchemyTooltips/AlchemyTooltips.lua:239: in function 'checkPotion'
|caaaaaa<Locals> itemLink = "|H0:item:76827:30:3:0:0:0:0:0:...", id = 132608, mainID = 76827, effect1 = "RavageHealth", effect2 = "RavageStamina", calculation = 2, BestCombination = [table:2] </Locals>|r
user:/AddOns/AlchemyTooltips/AlchemyTooltips.lua:305: in function 'SetBagItem'
|caaaaaa<Locals> self = ud </Locals>|r
EsoUI/Ingame/Inventory/InventorySlot.lua:2043: in function '(anonymous)'
|caaaaaa<Locals> inventorySlot = ud, bag = 1, index = 91 </Locals>|r
EsoUI/Ingame/Utility/ZO_SlotUtil.lua:14: in function 'RunHandlers'
|caaaaaa<Locals> handlerTable = [table:3]{}, slot = ud, handlers = [table:4]{}, i = 1 </Locals>|r
EsoUI/Ingame/Inventory/InventorySlot.lua:2404: in function 'ZO_InventorySlot_OnMouseEnter'
|caaaaaa<Locals> inventorySlot = ud, buttonPart = ud, listPart = ud </Locals>|r
(tail call): ?
(tail call): ?
ZO_StackSplitSource_MouseEnter:3: in function '(main chunk)'
|caaaaaa<Locals> self = ud </Locals>|r