Error explanation

Hello @Papad

Try to set breakpoint (Right-click on operator) on filter examples or set role operator (breakpoint before) and run the process to see if the attribute is coming into the operator, if not then you might look into the flow before this and see if that attribute is available or getting filtered out somewhere.

Usually this happens because there is some kind of filter condition that is causing the attribute to be excluded somewhere earlier in the process.  Another culprit can be the name of the attribute has been changed slightly (i.e., attribute names are case sensitive so even having one character different can cause this problem).

For me this mostly occurs when I use "Select Attributes" to remove Attributes but forget to check "Invert Selection"

@varunm1 @Telcontar120
@Edin_Klapic
Thank you all for your answers. Something went wrong with the attribute name, I renamed it and it worked perfect.
I don't know if it is a general problem or it just happened for other reason, but when I had the error, the repository had the same name with one of the attributes.
Do you think that this is the reason that error appeared?

As Edin mentioned, there might be multiple reasons for that, can you provide the attribute name you used if possible? Or you can check the points mentioned in Edin post

@varunm1
@Edin_Klapic
I think that when I copied the name to use it into filter examples and set role it had more spaces becauses of the " " characters. So I don't think that there was something else that affected it.
Thank you both for your answers.