Is my fast valid if I swallow pus with my saliva due to suffering from constant rhinitis, nasal congestion, and pus in my throat?

Whoever swallows phlegm or vomit while able to expel it, breaks their fast according to the Shafi'is. As for the Hanbalis, they hold that swallowing phlegm after it reaches the mouth breaks the fast. The Hanafis believe that sniffing mucus from the nose and swallowing it does not break the fast, nor does swallowing saliva that exits the mouth if it remains continuous with it; however, if it becomes disconnected, then reintroduced and swallowed, it breaks the fast. As for the Malikis, swallowing vomit or regurgitated matter while able to expel it breaks the fast, and they differed concerning phlegm, with the relied-upon opinion being that it does not break the fast whatsoever. The more cautious approach is to adopt the view of the Shafi'is and Hanbalis, unless doing so becomes difficult.