The third parameter of %SCAN is not between 1 and the length of the second parameter.
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Cause . . . . . : The third parameter of %SCAN, representing the starting position within the source string, must at least 1 and cannot be greater than the length of the source string (the second parameter). The starting position defaults to 1.
Recovery . . . : Correct the value of the third parameter, or remove the third parameter. Compile again.
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