is there a limit to the number of files we can download in a day?

Hi Jessica.  These are the Terms & Conditions for the Adobe Document Cloud.

The only thing I could find that might be relevant is section 6.2

6.2 Throttling. You agree to work with Adobe to create a plan to manage any spikes in demand for system resources driven by your use (“Spikes”). In the absence of such collaboration, you agree that Adobe may throttle or otherwise queue your Services-related transactions to manage any Spikes.

If this is what is happening, then it should free up for you in time.   Does the download freeze, or does it cancel out and close the dialog window?  If the former then leave it to sort itself out.  Otherwise close the window and try again, and unless it stops with an error message, let it run.

Where are you located?  Is it somewhere that might have busy periods like the start of the working day?  It might be better in your evening time.   I am also wondering if the document cloud uses the same Adobe servers as Generative Fill and Firefly because we know they have been swamped on occasions and locking some users out.