Hi Carolitaa,
We are sorry for the delay in response to your query.
As mentioned that you have already tried with different web browser and it still didn't work. So could you confirm is it a secured network (office network) you are working on?
You may check couple of things mentioned below-
1- Combine PDF has a limitation for number of files to be combined. You can only select maximum 12 files at a time to combine. Though file size is not an issue.
So if you are selecting more than 12 files then there would be a problem loading them.
2- If this is not the case, then you may check with a different internet connection for testing purpose. Or if there is any internet security software then turn it off for a while and check back.
[Antivirus software can help protect your computer against viruses and other security threats. In most cases, you shouldn't disable your antivirus software. If you have to temporarily disable it to install or activate other software, you should re-enable it as soon as you're done.]
Regards,
Akanchha