Custom validation only have one action: block. If users' enter don't match the rule which you added to the list then the form submission will be blocked.
One list may have one or multiple rules and every rule may have its own setting. This requires you set right value when add rule to your list.
Create custom validation list and add rule
Add age rule to list and requires age at least 18
Add two rules to list to limit Zip code start with 44
Add two rules to list to limit Mobile Phone must start with 10
Apply age rule list to DOB field
Apply list to Mobile Phone field
Apply list to Zip Code field
when submit form
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