Change of theme back to standard after reboot

I have downloaded a new Theme from the Personalize app and applied it to my MX4 with 4.04U, but every time I reboot the phone reverts to the standard theme.

Anyone experiencing the same?

So I have flashed Flyme 4.04A onto the phone and opened system privileges, but I am still not able to make a new lock screen wallpaper or a change of theme survive a reboot. What do I need to do in order to get this to work???

Edit: I deleted my downloaded Ubunblue theme and tried a different one. Lo and behold, it worked (fingers crossed)!

Good to hear it’s solved! ;)

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