Thank you very much for your answers!
I have followed your suggestions. The hosting support says that the website is working normally. A firewall is not installed and the preloader effect has been disabled. Unfortunately, the problem still occurs.
I would like to describe it in more detail here and it usually happens in this order:
- the page loads without problems on the first visit.
- Visiting a subpage, it usually also loads.
- If you visit a second subpage, only the loading symbol appears
- After closing the tab and reloading the page, only the loading symbol appears.
- If you delete the cache and reload the page, it starts again at the first point.
The problem occurs on iOS, Windows, Safari, Chrome, Firefox, Explorer etc.
The interesting thing is that you can see that the website is loading on the cell phone, but the loading symbol is superimposed. You can clearly see the website in the lower area. I have attached a corresponding screenshot.
I look forward to your help!