Try this first:

1. Refresh the license data

Go to WordPress Dashboard → Crocoblock → License
Press Ctrl + Alt + D (Windows) or Control + Option + D (Mac)
Click Delete License Data
Re‑enter your license key and try updating again.

2. If it still fails

Temporarily disable cache/security plugins
Or delete the plugin and reinstall it manually from your Crocoblock account.
About the old licenses you can’t remove: that can happen when the license data is stuck. The Delete License Data step often clears those as well.