Function that returns instruments name

William Roeder  
Luandre Ezra: My Magic number consist of MagicNumber = MagicEA + magicInstrument + magicSymbol + magicPeriod.

Magic number only allows an EA to identify its trades from all others. Using OrdersTotal/OrdersHistoryTotal (MT4) or PositionsTotal (MT5), directly and/or no Magic number/symbol filtering on your OrderSelect / Position select loop means your code is incompatible with every EA (including itself on other charts and manual trading.)
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          MagicNumber: "Magic" Identifier of the Order - MQL4 Articles (2006)
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You need one Magic Number for each symbol/timeframe/strategy. Trade current timeframe, one strategy, and filter by symbol requires one MN.

If trading multiple timeframes, and filter by symbol requires use a range of MN (base MN plus timeframe).
          Why are MT5 ENUM_TIMEFRAMES strange? - General - MQL5 programming forum - Page 2 #11 (2020)