A problem with a comparison block

I'm using a comparison block "LE". The block does not generate an output although the condition of the comparison is correct and all the contacts before the "EN" of the block is true. I tried connecting the "EN" directly to the power rail in the ladder but the same problem exists. What may be the cause of such problems?

Can you post the code here? I assume you are using S7.

What may be the cause of such problems?

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A "double-coil" - reusing the same output BELOW the comparison block, where another rung turns off the output. Remember that the PLC will do what it was LAST told to do.

Is the program block (or subroutine) that contains the comparison being scanned (or called from the main program)?