Restart worked for me for this stuck loading.

all handled via the Umbrel telegram ;)

iirc you fixed via System > Restart?

My recommendation was: First step check your Bitcoin Node app and that it is fully synced all recent blocks,

then I'd reboot Umbrel via System > Restart this accomplishes restarting lightning and all services,

if it finished resyncing recently you may need to wait a little while for Lightning to finish syncing-

otherwise can review debug log for any errors- can post it in the Telegram, send it to me directly for review here if you'd like or can use chat on Umbrel.com if you prefer to review debug logs or if you ever have any other questions!

The magic power cycle prevailed