# A valid authorisation token is missing error

#### 1. Try pasting the key again

This error usually appears because the license key has not been pasted correctly. 

Please try and paste the key again, and make sure there are no spaces at the beginning, end, or in the middle of the key.

The key should start with a "2-" or a "3-" so please include the whole key starting from here. 

**Note:** "3-" keys [require version 2.18.4](https://docs.portainer.io/2.33-lts/faqs/licensing/why-isnt-my-3-license-key-working) or newer.

#### 2. Try to refresh your browser

This error may also appear when there are caching issues. Please try refreshing your browser or close your browser and try again.