Serverless and AWS deploy issue

Question

I have to update a website on aws using serverless deploy. This website were not created by me, it's the first time I work with serverless and AWS solutions.

I have the source code, deploy files, etc, from the last person in charge.

I run a before-deploy.js script to create all local files, check them to see if the updates went ok. Everything's fine.

But anytime I try to deploy using the simple command "serverless deploy", it fails printing this error :

CREATE_FAILED: MainStaticSite (AWS::S3::Bucket) “mywebsite.com” already exists

I don’t really understand this error, as I know the website already exists but I just want to update it. I tried more specific commands like :

serverless deploy -v --stage production --region eu-west-1

But this one only shows this output :

Framework Core: 3.10.1 Plugin: 6.2.0 SDK: 4.3.2

PS

And doesn't updates the website.

I changed the keys on AWS, maybe it's because of this ?

Looks like he doesn’t want to overwrite the existing files, but no idea why. If someone has an answer or a lead.

Thank you :)