Checking if an Entity Attribute Column Contains a Value

Dear community,
I want to check if an entity attribute column contains a value.
So I basically have a text field where the user enters an account number, and then a subsequent calculate field to search through the same_outlet_acc column of the entity list (which is supposed to contain string of some options [accounts] selected through multiple-select question at entity creation) to see if any field in that column contains the account number entered in the text field.

Below is how my entity list table looks:

Is my calculation correct? Because it returns nothing instead of 'yes' or 'no' and I'm not able to figure it out.
if(count(instance('visited_agents')/root/item[contains(same_outlet_acc, ${acc_number})]/same_outlet_acc) > 0, 'yes', 'no')