Describe the bug
As mentioned in the title.

To Reproduce
Have gears with the same name, e.g. Tier set piece in LFR and Normal, etc.

Version:

• wow retail 10.1.5
• Server locale region: TW
• OS: Windows 10

Additional context

2x xMerchant/core.lua:299: attempt to perform arithmetic on local 'count' (a nil value)
[string "@xMerchant/core.lua"]:299: in function <xMerchant/core.lua:256>
[string "@xMerchant/core.lua"]:1054: in function <xMerchant/core.lua:1047>
[string "=[C]"]: in function `MerchantFrame_Update'
[string "@FrameXML/MerchantFrame.lua"]:50: in function <FrameXML/MerchantFrame.lua:42>

Locals:
limit = 74
(for index) = 2
(for limit) = 4
(for step) = 1
bagID = 2
numSlots = 32
(for index) = 14
(for limit) = 32
(for step) = 1
slotID = 14
itemID = 202543
count = nil
currency = 1
(*temporary) =

{
192999 = 1
202540 = 1
193809 = 1
202541 = 1
殘留的靈魂碎片 = 0
奇特的硬幣 = 136
202542 = 1
鬥陣金幣 = 1196
上古法力 = 932
宇宙靈流 = 94398
灌能紅寶石 = 100
商人的標幣 = 975
時朽文物 = 0
腐化死亡之翼的精華 = 0
204211 = 1
文物碎片 = 0
198322 = 1
黑暗微粒 = 0
大廳資源 = 57040
龍石 = 2000
油料 = 185
銀白十字軍表揚令 = 124
勇士徽印 = 39
高塔知識 = 0
194879 = 1
193768 = 1
200642 = 1
風暴符印 = 30
血腥硬幣 = 1154
朦朧的阿古岩 = 2000
要塞資源 = 10000
193738 = 1
首創者的暗語 = 1997
感激禮賜 = 409
元素溢流 = 102019
宿命徽印 = 6
頂尖水晶 = 125636
征服點數 = 0
超因果薄片 = 4805
覺醒精華 = 930
破碎命運徽印 = 0
榮勛軍團軍功獎章 = 566
盲目之眼 = 889
151116 = 1
202573 = 1
冥魄 = 11263
永恆硬幣 = 85522
202543 = 1
次級好運符咒 = 276
美食主義者的獎勵 = 38
193519 = 1
罪孽石碎片 = 15623
榮譽點數 = 3
冥魄餘燼 = 107
腐化的紀念物 = 17184
海員古幣 = 114
聚合幻象 = 306372
托巴拉德表揚徽章 = 18
暗月獎品券 = 976
軍團之殞戰爭物資 = 588
63378 = 1
稜光法力珍珠 = 826
巨龍群島補給品 = 29881
戰亂命運徽印 = 3
戰爭物資 = 78637
世界之樹印記 = 28
奈奧羅薩回音 = 35960
虛空裂片 = 38273
靈魂燼火 = 5536
編目研究 = 30349
鐵爪徽章 = 255
靈魂灰燼 = 41736
長者的好運符咒 = 0
時光扭曲徽章 = 25
202539 = 1
淬鍊命運徽印 = 2
193773 = 1
泰坦殘質 = 0
魔古的命運符文 = 4
庫存靈魄 = 56726
戰鑄徽印 = 0
}
(*temporary) = 202543
(*temporary) = 2
(*temporary) = "attempt to perform arithmetic on local 'count' (a nil value)"
currencies = {
192999 = 1
202540 = 1
193809 = 1
202541 = 1
殘留的靈魂碎片 = 0
奇特的硬幣 = 136
202542 = 1
鬥陣金幣 = 1196
上古法力 = 932
宇宙靈流 = 94398
灌能紅寶石 = 100
商人的標幣 = 975
時朽文物 = 0
腐化死亡之翼的精華 = 0
204211 = 1
文物碎片 = 0
198322 = 1
黑暗微粒 = 0
大廳資源 = 57040
龍石 = 2000
油料 = 185
銀白十字軍表揚令 = 124
勇士徽印 = 39
高塔知識 = 0
194879 = 1
193768 = 1
200642 = 1
風暴符印 = 30
血腥硬幣 = 1154
朦朧的阿古岩 = 2000
要塞資源 = 10000
193738 = 1
首創者的暗語 = 1997
感激禮賜 = 409
元素溢流 = 102019
宿命徽印 = 6
頂尖水晶 = 125636
征服點數 = 0
超因果薄片 = 4805
覺醒精華 = 930
破碎命運徽印 = 0
榮勛軍團軍功獎章 = 566
盲目之眼 = 889
151116 = 1
202573 = 1
冥魄 = 11263
永恆硬幣 = 85522
202543 = 1
次級好運符咒 = 276
美食主義者的獎勵 = 38
193519 = 1
罪孽石碎片 = 15623
榮譽點數 = 3
冥魄餘燼 = 107
腐化的紀念物 = 17184
海員古幣 = 114
聚合幻象 = 306372
托巴拉德表揚徽章 = 18
暗月獎品券 = 976
軍團之殞戰爭物資 = 588
63378 = 1
稜光法力珍珠 = 826
巨龍群島補給品 = 29881
戰亂命運徽印 = 3
戰爭物資 = 78637
世界之樹印記 = 28
奈奧羅薩回音 = 35960
虛空裂片 = 38273
靈魂燼火 = 5536
編目研究 = 30349
鐵爪徽章 = 255
靈魂灰燼 = 41736
長者的好運符咒 = 0
時光扭曲徽章 = 25
202539 = 1
淬鍊命運徽印 = 2
193773 = 1
泰坦殘質 = 0
魔古的命運符文 = 4
庫存靈魄 = 56726
戰鑄徽印 = 0
}
XMERCHANT_LOGD = defined @xMerchant/core.lua:78
XMERCHANT_DEBUG_TAGS = {
[Faction] = 0
[AltCurrency] = 0
[CurrencyUpdate] = 0
[CurrencyFrames] = 0
CurrencyUpdate = 0
[MerchantItemInfo] = 0
[GetKnown] = 0
[GetError] = 0
[FactionsUpdate] = 0
}
GetContainerNumSlots = defined =[C]:-1
GetContainerItemID = defined =[C]:-1
GetContainerItemInfo = defined