synology access

I am running Big Sur 11.6 on my iMac. I have been able ot access my Synology NAS both via Finder and directly by typing the NAS IP address in Safari. A week ago, Safari says it can't connect. The NAS is still visible through Finder, I can access all the files, but I need to run an app directly via Safari. I tried Chrome same problem. I have rebooted everything several time, no change. I am not sure what changed in the last week, but would appreciate some tips as to why Finder has no issue seeing the NAS, but the IP address in the browser does not work anymore.