filex completely disappear from /dist

[richardgraft]

I have an urgent and strange issue with a site build using this tool.

Running yarn dev seems to completely erase all files from the /dist folder and present a bug in the console:

`> [email protected] build:rollup
> NODE_ENV=production rollup -c


src/scripts/theme.js, src/scripts/sections/*.js → dist...
[!] TypeError: [conf.input].flat is not a function
TypeError: [conf.input].flat is not a function
    at Object.options (/Users/madebyrichard/Dropbox/Work/2021-clients/Emmy London/emmy-london/node_modules/rollup-plugin-multi-input/dist/plugin.js:137:15)
    at /Users/madebyrichard/Dropbox/Work/2021-clients/Emmy London/emmy-london/node_modules/rollup/dist/shared/rollup.js:20978:43

ERROR: "build:rollup" exited with 1.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.`

Would be great to know what is causing this issue. thanks