Php when visiting subdomain/installer gives 404 error

Your software
My PHP version is : 7.4.2
My MariaDB version is (delete as applicable): 10.3.31

Updating/Installing Errors
I am : Installing
Upgrading/installing via / Command Line

These errors are showing in the installer :

(subdomain).mydomain.com/index.php/installer gives 404 error

These errors are showing in the Mautic log :

No Errors showing/no log files

These errors are showing in the upgrade_log.txt file (located in the root of your Mautic instance when an upgrade has been attempted - ensure you remove or redact any sensitive data such as domain names in the file path) :

No errors showing/no log files
Your problem
My problem is : When I visit mautic.mydomain.com I get a resolve()); on the screen, but nothing else, and the installer is showing a 404. Verified www-data has all permissions. New to linux/DigitalOcean, but files are all there, and my SuiteCRM is running on the same server. Any ideas where to start?

Steps I have tried to fix the problem :

do you have any solution for that problem… i have same problem… its missing installation folder…

I probably misunderstood your question, but if you have Mautic on a subdomain like mywebsite.com/mautic, you manually have to add/change this in your .htaccess file:

    <If "%{REQUEST_URI} =~ 
m#^/mautic/(index|index_dev|upgrade/upgrade)\.php#">
        Require all granted
    </If>

If you put your Mautic installation on another subdomain name than /mautic/, like /crm/ or something creative, use that of course.

In general 404 errors after installation could be caused by file permission errors, for example if you went through the installation process via command line as root, instead of as user.

hello

I been installing that in different ways and never had installation folder in Mautic directory… dont know why i have checked permissions and was all good. When i open browser and go to Mautic installation automaticly from let say domian.com/index.php is redirected to domian.com/installation/index.php but I had installation folder there and browser was empty 404 error.

Could that be issue cos i used Hestia panel as starting point??
sorry for my english

Make sure not to use -dis on .htaccess file