Lightsail - Adding a tag while the instance is already running

Hi.

As per the Lightsail documentation, we should be able to manage tags on instances after they been created. https://lightsail.aws.amazon.com/ls/docs/en_us/articles/amazon-lightsail-adding-tags-to-a-resource

There should be a Tags tab into the management page of the resource.
I can't see this tab. Everything else is there, except for "Tags" ....

Is a special IAM role missing on my account to manage tags on Lightsail resources ? I checked and didn't see any roles about this...

Thanks.