Installation and Upgrade • Backup not working after upgade 8.8.15 to 9.0.0

After upgrading to 9.0.0 (latest patch) backup stopped working.
There's the error "Read/write error: please verify file and directory permissions." on the backup tab/Network Modules NG
The permissions are correct (already tried to run chown zimbra:zimbra -R on the backup dir).
Tried to start a new backup. Confirmed zimbra user has access to read/write the new location.

The new backup also fails:
This is an automated notification from Backup about Smart Scan.

Operation Smart Scan Failed.

Operation Id: dd7d4437-b38e-44dd-821c-e68ecb4e99c2
Operation Host: mail.xxxxxx.pt
Operation requested by: admin@xxxxxxx.pt

Network Modules NG Version: 3.19.0
Network Modules NG commit: e7a432615a6959e2979564c713451d75fe8d051f
ZAL Version: 2.39.0
ZAL commit: 6f921881d2e74c3d6437d67e762f4b5caf225eb7
Zimbra version: 9.0.0_GA_4583 20231201111812 20231201-1146 NETWORK


-- exceptions --
- Write permissions missing on backup directory: /opt/zimbra/backup
Operation parameters:
requesterAddress = admin@xxxxxx.pt
additionalNotificationAddresses = admin@xxxxxx.pt
origin = SOAP
isDeep = false
createFakeBlob = false
Last progress info:
--
Account scanned: 0/??
Account updated/new: 0/0
Item scanned: 0
Item updated/new/unique: 0/0/0

I opened a support case with Zimbra, they gave me no solution so far.

Statistics: Posted by scantec — Thu Jan 11, 2024 2:46 pm

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