I'm sorry to hear you are having difficulty with the Adobe Stock website. We don't currently have an outages or reports that this is a global issue. Please try the "steps" below to troubleshoot your issue.
Clear your browser history and restart your browser.
Anti-virus may be blocking functionality on the site. Please check your anti-virus settings and confirm that Adobe is in the allow list.
To troubleshoot, disable all browser extensions, then add them back one by one to determine which may be causing the issue.
If you are on a corporate network your IT department may have restrictions in place that are preventing you from downloading. Try downloading from a different network.
Please post your results as what you discover may help others that might encounter this issue.