Problems re-installing atom

Hello, I had Atom on Ubuntu, but it always opened two strange files when I started it. I followed the instructions of user “baloe” here: Whenever I start Atom it opens a file weird file, but I probably made a spelling mistake or accidentally deleted a part of the line. Since then, I could not open Atom.

I un- and re-installed it, and reverted my changes on the “/var/lib/snapd/desktop/applications/atom_atom.desktop”-file. But since then, Atom only opens a small, white console which gives me the following error:

index.js:129 Error: EACCES: permission denied, open ‘/home/paul/.atom/compile-cache/less/df1b7fbc57dbeed23a8f1f8de95b4dfebcc06066/imports.json’
at Object.openSync (fs.js:453)
at Object.func [as openSync] (electron/js2c/asar.js:138)
at Object.writeFileSync (fs.js:1246)
at Proxy.writeFileSync (/usr/share/atom/resources/app/static/:11)
at LessCache.writeJson (/usr/share/atom/resources/app/static/:14)
at LessCache.setImportPaths (/usr/share/atom/resources/app/static/:14)
at new LessCache (/usr/share/atom/resources/app/static/:14)
at new LessCompileCache (/usr/share/atom/resources/app/static/:14)
at ThemeManager.loadLessStylesheet (/usr/share/atom/resources/app/static/:11)
at ThemeManager.loadStylesheet (/usr/share/atom/resources/app/static/:11)
at ThemeManager.requireStylesheet (/usr/share/atom/resources/app/static/:11)
at ThemeManager.reloadBaseStylesheets (/usr/share/atom/resources/app/static/:11)
at ThemeManager.loadBaseStylesheets (/usr/share/atom/resources/app/static/:11)
at AtomEnvironment.initialize (/usr/share/atom/resources/app/static/:1)
at t.exports (/usr/share/atom/resources/app/static/:1)
at setupWindow (index.js:175)
at window.onload (index.js:106)
handleSetupError @ index.js:129

I don’t know much about Ubuntu and i probably destroyed something. Please help me!