red exclamation mark "cannot confirm integrity"?

Hello

I made two backups that are stored locally!
(1.3 GB per backup)
So far, but in the Issue column there is a red exclamation mark "cannot confirm integrity"
What does the red exclamation mark "cannot confirm integrity" mean?

I found no nextcloud error logs!

I think the backups are complete! But haven't tried a restore yet!
I really wanted to know what the red exclamation mark means and whether the backups are ok!

I need HELP urgently !!!!!!

my data:
root server 1TB ssd
nginx docker-image as reverse-proxy

Nextcloud 23 ogrinal docker-image:
apache2 / stable-security, now 2.4.51-1 ~ deb11u1 amd64 [installed]
Apache HTTP Server

php --version
PHP 8.0.13 (cli) (built: Dec 2 2021 13:29:44) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.0.13, Copyright (c) Zend Technologies
with Zend OPcache v8.0.13, Copyright (c), by Zend Technologies

mysql --version
mysql Ver 15.1 Distrib 10.5.6-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

No repository file, test, or code entry point is identified in the report. Start by locating the backup integrity status implementation and reproducing the red exclamation mark with the stated local backups. Done means the indicator's meaning and the conditions for confirming or rejecting the backup are documented or corrected, with a restore check if required.