Change status based on "last modified time" field

[Florence_Dorsil]

Hello community,

I’m having a very very hard time finding out the perfect formula to activate my automation… :pleading_face:

Here the thing :
I offer a 14 days trial with my services and wanted to track this with airtable. Each time the status change, an email is sent to the client via automation. For exemple :

• New record :arrow_right: Confirmation email
• Service online :arrow_right: Validation email
• One week left :arrow_right: Reminder
• 14 days :arrow_right: Service is over - Email sent
• Service off :arrow_right: Upsell - Email sent

The point of entrance is airtable form, but the service is live once the field “update URL” which is a last modified field is updated. Here’s the formula :

IF({Interface supprimée}=1,“Interface supprimée :pensive: ”,
IF(DATETIME_DIFF(TODAY(), {Update URL},‘days’) >=14, “C’est fini”,
IF(DATETIME_DIFF(TODAY(),{Update URL},‘days’) >=7, “Plus qu’une semaine”,
IF(DATETIME_DIFF(TODAY(),{Update URL},‘days’) >=1, “Phase test”,
IF(DATETIME_DIFF(TODAY(),{Update URL},‘days’) =0, “Nouveau client” )))))

Problem is, this formula work fine when set with “date” but don’t work anymore when set with “last modified”. Date format are identicals, date are identicals :

When set on “date” :

When set on “last modified time” :

Anyone can help ??