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1. 1. Validate mandatory query params
      
      1. first_name
      2. last_name
      3. birth_date
   2. Validate optional query params
      1. tax_id
      2. birth_certificate
      3. phone_number

Logic

1. if tax_id is not null and age>=16
   1. search via tax_id + first_name + last_name
2. if tax_id is null and age>=16
   1. search via first_name + last_name + birth_date
3. if age<16
   1. search via birth_certificate + birth_date

Calculate age

age = MONTHS_BETWEEN (now(), $.birth_date) / 12

Search existing MPI entity

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