The formula calculates the date difference between now and a column called ‘Echeance’ and if the difference is smaller that 31 days and the columns ‘Echeance’ and ‘FAIT’ are not blank, it returns true.

Now, I get the following error : Argument 3 of date_diff is not a date.

The formula used to work flawlessly without issues and I didn’t change it.

‘Echeance’ is the result of the following formula: if(isblank(field(‘Durée’)),‘’,date_interval(field(‘Durée’))+field(‘Date’))

so it is either blank or a date. I don’t understand why it is suddenly not considered a date anymore or is the fact that some cells are blank considered a problem now.

I use an empty string so it doesn’t calculate a date when ‘Durée’ (duration) is empty but I think it might be creating a problem with the formula as it sees it as text.

If it doesn’t work, then maybe you could share with me privately the overview of all fields, and then I will try to rebuild the scenario and check the formula once again.

Yes, this one worked without an error. However, it does give TRUE even when the difference between now() and ‘Echeance’ is bigger than 31 so there is an issue for the logic of the what I intended to do.
Thank you still for helping.