after comment this in .htaccess #RewriteEngine on #RewriteCond %{HTTP_HOST} ^mautic.segredosdoprogramacasaverdeeamarela.com$ #RewriteRule ^/?$ “http://^(?!/(index\.php|index_dev\.php|app|addons|plugins|media|upgrade|upgrade_v3))(/(.*))$” [R=301,L]
WARNING! You are about to execute a database migration that could result in schema changes and data loss. Are you sure you wish to continue? (y/n)y
Migrating up to 20200815153711 from 20200220172041
++ migrating 20200227110431
-> CREATE INDEX dnc_channel_id_search ON lead_donotcontact (channel_id)
Migration 20200227110431 failed during Execution. Error An exception occurred while executing 'CREATE INDEX dnc_channel_id_search ON lead_donotcontact (channel_id)':
SQLSTATE[42000]: Syntax error or access violation: 1061 Duplicate key name 'dnc_channel_id_search'
In AbstractMySQLDriver.php line 106:
An exception occurred while executing 'CREATE INDEX dnc_channel_id_search ON lead_donotcontact (channel_id)':
SQLSTATE[42000]: Syntax error or access violation: 1061 Duplicate key name 'dnc_channel_id_search'
In PDOConnection.php line 80:
SQLSTATE[42000]: Syntax error or access violation: 1061 Duplicate key name 'dnc_channel_id_search'
In PDOConnection.php line 75:
SQLSTATE[42000]: Syntax error or access violation: 1061 Duplicate key name 'dnc_channel_id_search'
I changed my domain in Configuraiton “Site URL”. Are you getting a mautic login prompt? If not then I think it’s the web server. Usually in either Nginx or Apache there is a Server Name field that you should change, too. That’s what I had to changed when I did it.
Restore from backup and try again as your 3.1 upgrade failed.