@Savvytech this issue seems to be a bug in the npm cli. NPM had fixed this bug earlier but it seems like the issue has reappeared in the latest update.
There are bugs raised previously (ref: https://github.com/npm/cli/issues/1703#issuecomment-774684656) and it's mainly due to package name aliases. So, if you want to get rid of this issue then the simplest solution would be to not use package name alias.
Here's how to use gsap package without package name alias:
