I don't understand why SUMIFS function works with some columns in the same worksheets and for others it doesn't. This is my formula:

=SUMIFS(EURO;AGENZIE;"ABN";MESI1;"01")

where EURO, AGENZIE, ABN AND MESI1 are the name of some columns in the same sheet. The formula is needed to add the values in the EURO column when the condition in others columns is that they are equal to ABN (AGENZIE) and month is January (MESI1=01). Column AGENZIE had other values, and when they are used instead of ABN the formula seems to work. My question is: how the heck is possible that the same formula works depending on the value I use as condition? I don't get any error, only the result is zero when it should be <>0. Thanks for help me solve this problem