Hello, why in your opinion this validation rule is not working even if there are no errors?
I want users to be alerted when the value in the old contract field is empty AND the type detail picklist is one of the listed values.
AND( ISNULL(Amount_of_the_old_contract__c),
OR
(ISPICKVAL( Type_detail__c , "Migration - On-prem > SaaS - same product")),
(ISPICKVAL( Type_detail__c , "Migration - On-prem > SaaS - other product")),
(ISPICKVAL( Type_detail__c , "Migration - Hosted License > SaaS - same product")),
(ISPICKVAL( Type_detail__c , "Migration - On-prem > Hosted License - other product")),
(ISPICKVAL( Type_detail__c , "Migration - From a product to another one")))
Eric Praud (Activ8 Solar Energies) 
Forum Ambassador
Hi,
First, always use ISBLANK, not ISNULL. It has been deprecated well over a decade ago and is no longer support.
Second, can you ensure you are using the API names of the picklist values, not their labels. They can be different
Finally, your brackets are off, so the OR is only used for the first ISPICKVAL, the other ones are part of the AND statement, which is probably your issue here
AND( ISBLANK(Amount_of_the_old_contract__c),
OR(
ISPICKVAL( Type_detail__c , "Migration - On-prem > SaaS - same product"),
ISPICKVAL( Type_detail__c , "Migration - On-prem > SaaS - other product"),
ISPICKVAL( Type_detail__c , "Migration - Hosted License > SaaS - same product"),
ISPICKVAL( Type_detail__c , "Migration - On-prem > Hosted License - other product"),
ISPICKVAL( Type_detail__c , "Migration - From a product to another one"))
