Related to Custom Fields

Hi Team,

I would like to know what this below paragrah which is mentioned in your api documentation means.

If you’re not getting a result for the above query, there’s a chance that the field might have been created recently or it has been moved to a new infrastructure. To query on these custom fields, use ‘custom_string’ instead of the actual field label.

And how do i acheive my search with custom field if this is the condition.