Editing a single textbox edits the master page

[lucaspeinado.es]

Hello! I'm doing some flashcards to study, and it all went right until I got to a textbox, I wrote the stuff that I needed and then, the next textbox was with that text that I wrote before. When I edit any textbox with that content, all textboxes change, and also the master page one.

[walt.farrell]

Welcome to the Affinity forums, @lucaspeinado.es.

Please let us see a screenshot of the complete application window, with just the page you're editing visible in the workspace (not the others), and the Layers panel visible and showing us the layer you're working in when this happens.

Also, please tell us which macOS release you're using, and which Publisher release.