Not sending notification after failed backup v6.8

[aanyszek]

Hello,
i have issue: when remote backup fail with connection problem notification is not sending.

$ php artisan backup:run --only-db
Starting backup...
Dumping database topq...
Determining files to backup...
Zipping 1 files and directories...
Created zip containing 1 files and directories. Size is 408.88 KB
Copying zip to disk named remote-backups...
Copying zip failed because: Could not login with connection: xxx:21, username: xxxx.
Sending notification failed
Backup completed!

I expect to receive notification message with connection error to email or slack.

[Cannonb4ll]

Had the same issue, Laravel version 7 with this as an exception:

Target [Illuminate\Contracts\Mail\Factory] is not instantiable while building [Illuminate\Notifications\Channels\MailChannel].

[pms07]

Same issue occurred on production system Ubuntu 18.04 with PHP 7.2 but perfectly working fine on local system while testing (local system: windows 10 with PHP - 7.2