Runtime class of object "1" (index 1) in row "Row 0" is Number (long) and does not comply with its supposed superclass Non-Native KNIME

[ChrMavrom]

Hi everyone I am new to KNIME and I am straggling with some basic steps.
I am trying to do a join using 3 columns, 2 are numbers and one is string.
In table 1, key columns are Number (Integer) - I and in table 2 are Number (long) - L. I change the format of the columns before the join but I still get this error:
“Runtime class of object “1” (index 1) in row “Row 0” is Number (long) and does not comply with its supposed superclass Non-Native KNIME”
Any help or advice is highly appreciated.
Thanks

[darspir]

Hi @ChrMavrom ,
could you please attach the example workflow (without sensitive information), so we could take a look?
Thanks!