Validation errors on external application flow do not appear on the page the field sits on

Summary

Post code/zip code validation error appears on submit page

Content

Candidate experience is not great if they enter their post code/zip code in the incorrect format. The post code is on page one of the flow, and the error shows on the submit page (page 4). If the candidate receives this error, they have to click back three pages, amend, then forward three pages to submit. Pretty poor experience. Can the field validation warning appear on the page with the field on it?