Troubleshooting a publishing problem with a custom domain

Hello, I've got a publishing problem with a custom domain: I've added it to cloudflare when I check status it's all good with .wstd.io one not with custom domain and browser says DNS address could not be found.
Site: https://p-88903cad-7329-48c6-bab5-2be63ae75859.apps.webstudio.is/?authToken=516fe55e-6aef-440c-af79-d0c40c866f57&mode=preview
Custom domain: https://adriannachojnacka.pl/
Any tips ? What am I missing ?