Thanks. I’ve just un-enrolled from Advanced Protection in my Google account, which as you say, is separate from Device Protection in the device settings. I’ve also done a force stop of the Google Play app. I’ve read that it can take up to 24 hours for these protections to stop so I’ll let you know.
UPDATE
I waited a few hours, then managed to install Huawei App Gallery, then HMS Core, then finally Huawei Health App.
Thanks everyone 🙂