Start with a status check.

The icon is wrong

Run appicon resolve --explain NAME. The output names the source. Add an override if you want another match.

Remote icons do not load

Check your enabled sources in the status output. Cached icons continue to work offline.

The cache is too large

appicon cache stats
appicon cache prune

Pruning removes old cached files. It keeps your settings.

You found a bug

Include the output from appicon status and the name you tried. Remove API keys before posting.