No you replied to the correct post, but we posted simultaneously 
For upgrading, I manually changed the dipendencies of Ionic and Angular, but after seen the error, I reverted all to previous version and redo it like you said. I deleted package-lock.json and node_modules folder before doing npm install.
npm outdated shows nothing, it’s all at the latest version. I think it’s some misconfiguration problem, today I’ll try some solutions and let you know. Thank you for the response!