Web app auto-redirecting to the initial page on iOS problem (it should NOT redirect)

I have a web app for Android and iOS that opens a web page. The app works fine for Android and most of the iOS devices.

But for some reason, for some iOS users, the app automatically (randomly) redirects users to the initial page after a few minutes using the app.

A user opens the app on the initial page, clicks on a link for a different page, the user is reading the page, then for some reason the app redirects back to the initial page.

There's no JavaScript code that does redirect in the application, there's a service worker, but with no redirects.

It does not happen all times, but it does happen and annoys the users.

Any ideas on what could be happening?

from Web app auto-redirecting to the initial page on iOS problem (it should NOT redirect)