Hey @LLawiet
The build image you are using is running an outdated and incompatible version of Node.js.
Using one of the methods outlined in the Manage Build Dependencies documentation to updated the version of Node.js used is the simplest.
Another option is to deploy a new site using the latest build image which runs Node.js v16. If you are using a custom domain, you could then remove them from the current site and add them to the new site.
If you have any questions, please don’t hesitate to reply.