count contacts in entity

[yuri]

The formula is calculated on the record save. Try to re-save the record or on the list view: select record > Recalculate Formula.

[McBrumm]

I have linked an entity to a contact. They have a n:n relationship.
Now I would like to enter a formula in the entity that counts the existing contacts in the data record.

I use the following formula
averkufe = entity \ countRelated ('contacts');

The results are wrong. If I enter a contact, it counts 0, if I remove it and the field is empty, it counts 1. What's the correct formula? thanks