If you want to apply conditional validation on 'Voter Age' or 'Member Age' then need to add this input greater than '17'.
{{userForm.controls?.age?.errors?.greaterThan.message}}
Retirement Age should be greater than age
{{userForm.controls?.retiermentAge?.errors?.greaterThan.message}}
If you want to apply conditional validation on 'Voter Age' then need to add 'Age' field greater than '17'.
{{userForm.controls?.voterAge?.errors?.greaterThan.message}}
Shows custom message
{{userForm.controls?.otherAge?.errors?.greaterThan.message}}