Solved Filezilla Not Uploading File

I am having a frustrating, weird problem. I use Filezilla to FTP my files to my website. It worked fine all day for all files. But when I try to FTP a new Index file, it's there but not there. I get this status: Status: File transfer successful, transferred 12,248 bytes in 1 second. That's the right byte count. But the Index file in the Remote Site Filelist is the old Index file with the old Index file byte count. When I go to the website the old file is what opens. But when I select View/Edit the file in the Remote Site Filelist the new Index file is what is opened for editing.

How is Filezilla "viewing" the new file while not replacing the old file in the Filelist and on the website? I even tried renaming the old Index on the Remote Site, FPTd the new Index again, and it still is showing the old Index file in the Filelist. And it's still the old Index file that's opened when I go to website.

Can someone kindly tell me what I'm doing wrong or what to do?
Thank you.

Thank you jmarket and gus for your replies (and yes, I disconnected Filezilla a few times). I finally thought of calling my host support. They tried all sorts of things, including running some update on their server to propagate my file, none of which worked. I finally had to send him my file for him to load. Then he had me run CCleaner to clear the cache. Now I can access the file. I believe there is/was something messed up on their side - I don't know how the cache could mess up the Remote Site Filelist on two FTP programs (I installed Core FTP to eliminate Filezilla as being the problem and Core FTP had the same wrong Index version in the Remote Server Filelist). But for now it's updated so I'll have to see the next time I have to change the Index, which won't be until next year.
Thank you both again for your very quick help. I truly appreciate it.

It actually happened again last night with a different html file. Perhaps the problem is related to FF using cache instead of going to the website. But that doesn't belong here - I'll open another thread for that. So I'll mark this as solved. Thanks, again.