Calculate Iterate Levels in M

Hi  ALL! 
I tried to calculate in power query levels for my accounts to calculate all of them later .
I used this code to do it , but is`s don`t work , maybe someone know what could be wrong? 

let
    MappingRules = #"MappingRules",  

    Level1 = Table.AddColumn(
        MappingRules, 
        "Level", 
        each if List.ContainsAll(Balance[FinalAccount], { [SourceAccount] }) then 1 else null, 
        Int64.Type
    ),

    CheckIfCompleted = List.Contains(Level1[Level], null),

    IterateLevels = List.Generate(
        () => [Table = Level1, LevelNum = 1],  
        each CheckIfCompleted,  
        each 
            let
                CurrentTable = _[Table],  
                NextLevelNum = _[LevelNum] + 1,  

                UpdatedTable = Table.TransformColumns(
                    CurrentTable,
                    {"Level", each 
                        if _ <> null then _ 
                        else if List.ContainsAll(CurrentTable[ComponentAccount], 
                                                 Table.SelectRows(CurrentTable, each [Level] = _[LevelNum])[SourceAccount]) 
                             then NextLevelNum 
                             else null, 
                        Int64.Type}
                ),

                UpdatedCheck = List.Contains(UpdatedTable[Level], null)
            in
                [Table = UpdatedTable, LevelNum = NextLevelNum, CheckIfCompleted = UpdatedCheck],  
        each _[Table]  
    ),

    FinalLevelsTable = List.Last(IterateLevels)
in
    FinalLevelsTable