The new and better ‘WordPress on App Service’

I have an App Services (wordpress) mcr.microsoft.com/appsvc/wordpress-alpine-php:8.2 - PremiumV3 (P2v3)
We had some problems with the application gateway (502 and 504), but apparently it was fixed.
But we have another more serious problem: we can't get into the wordpress backoffice <website>wp-admim - it takes "hours" to get in. We've already opened a support case and haven't had any coherent answers yet.

Here's the list of plugins we have:

advanced-custom-fields inactive none 6.2.7
acfml inactive none 2.0.5
akismet inactive none 5.3.2
all-in-one-wp-migration inactive none 7.81
app_service_email inactive none 1.0.0
child-theme-configurator inactive none 2.6.6
classic-editor inactive none 1.6.3
contact-form-7 inactive none 5.9.3
contact-form-7-multilingual inactive none 1.2.2
contact-form-cfdb7 inactive none 1.2.6.8
custom-post-type-ui inactive none 1.15.1
disable-emojis inactive none 1.7.6
divi-ajax-filter inactive none 3.0.1
brain-conkit inactive none 2.4.17
cf7-styler-for-divi inactive none 2.1.1
divi-machine inactive none 6.1.6.2
divi-mobile inactive none 1.8.2
duplicator inactive none 1.5.8.1
password-protected inactive none 2.7.1
pdf-embedder inactive none 4.7.1
really-simple-ssl inactive none 8.0.0
say-what inactive none 2.2.2
simple-divi-shortcode inactive none 1.0
wp-smushit inactive none 3.15.5
supreme-modules-for-divi inactive none 2.5.3
svg-support inactive none 2.5.5
updraftplus inactive none 1.24.2
w3-total-cache inactive none 2.7.0
wow-divi-carousel inactive none 2.3.3
wp-debugging inactive none 2.11.23
wp-mail-smtp inactive none 4.0.1
wpml-media-translation inactive none 2.7.3
sitepress-multilingual-cms inactive none 4.6.9
wpml-string-translation inactive none 3.2.9
wpvivid-backuprestore active none 0.9.99
wpvivid-imgoptim inactive none 0.9.21
wpvivid-backup-pro active none 2.2.23
duplicate-post inactive none 4.5
wordpress-seo inactive none 22.3
a-wpvivid-restore-mu-plugin-check must-use none
advanced-cache.php dropin none
db.php dropin none
object-cache.php dropin none

Any suggestions - there's someone here with the same symptom.