It's possible that there was an issue with the software installation or the update that is causing the error. Here are some troubleshooting steps you can try:
# Check your internet connection: Make sure that your wifi network is stable and strong enough to download updates. You can try resetting your router or moving closer to it to improve the signal.
# Try a different USB flash drive: If the flash drive you used to install the software is faulty or not compatible with the Steam Deck, it could cause issues. Try using a different one to see if that helps.
# Reinstall the software: You may need to reinstall the software again to fix any issues that may have occurred during the installation process. Make sure to follow the steps carefully and double-check that you have the correct version of the software for your Steam Deck.
# Contact Steam support: If you have tried the above steps and are still experiencing issues, you can contact Steam support for further assistance. They may be able to provide additional troubleshooting steps or help you with a repair or replacement if necessary.