Site refuses to update on server

Hi.
My site on https://wideopenwindows.be/Bookworm refuses to update when I change something, for instance with CSS. On localhost everything functions normally. FTP seems to be working too. Caching and pipelining has been disabled. The hosting company says everything is ok on their side. Please help me out. Thanks.

@TonHaarmans, Without proper information there is not much we can do apart from mind guessing...

Please have a look at these suggestions on how you can enrich your question.

I assume you have you ruled out browser side caching?

Can you restart the web server?

Have you interrogated the data directory to double check what’s there?