Hello @Gerardo Reyes
Thank you for reaching out to Microsoft Q&A.
I understand that you're having trouble with the theme settings not saving when you re-enter your portal. I tested it on my end, and the theme settings are applying correctly for me.
Please try saving the changes again on your side and ensure that you click on Apply after making changes.
If the problem persists, let us know!
Regards,
Goutam Pratti.
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