Jest cannot find core-js module

I get an intermittent error with jest -

Cannot find module 'core-js/modules/es.symbol.description' from ''

I seem to get this when trying to access global within jest. I also got this when trying to use a fetch mock library.

After checking core-js library, I cannot find a file with that name.

I have no idea how to sort this.

We are using core-js 2.6.9 and vue 2.6.6