Just two quick tips to look at:
1. If your startup command relies on a path to a containerd socket, make sure containerd is actually running, and that the sock file exists. Restart containerd if not.
2. If you are modifying the bridge IP (so it doesn’t conflict with another range on your routing, etc), check the input. Did you end it with .0, when you meant .1? Try that. Also make sure you fed it a range like /24 etc.