Shelly 2.5 w/ ESPHome running very hot. Trying to revert firmware, but can't

So my Shelly is running pretty hot. I assume its because its in a black enclosure, outside, with essentially no airflow. After installing it, I’m seeing lots of mentions of heat issues with the 2.5. However, I’d like to go back to the Shelly firmware, just to rule out something I’ve done with the ESPHome config. Any time I try to reflash the firmware, it says that it’s out of storage.

How can I flash back to the Shelly firmware, or even Tasmota?

Google search for restore shsw 25 firmware,
download original firmware,
then flash it with esptool or similar tools - I followed this guide recently