Hello Bence,

Thank you for reaching out to us.

Here is a custom validation script for new booking form

<script>
window.ameliaActions = {
customValidation: function (success = null, error = null, data) {
    console.log('customValidation HOOK')
    console.log('------------')
//you can check existing rules here
    console.log(data.rules)
    const customValidator = (rule, value, callback) => {
      if (!value.includes('@health-check.at')) {
        callback(new Error())
      } else {
        callback()
      }
    }
    // this example is for email input field
    data.rules.email.push({required: true, message: 'CUSTOM MESSAGE', validator: customValidator, trigger: 'submit'})
  },
}
</script>

Please let me know if that helped you.