500 error. Is it possible to fix it?

[sajdis]

Today I found that I can't access my prestashop. I turned on debug mode and I found this error on that photo below. Does anyoen knows how to fix it? Everything was working fine. I haven't made any changes a few weeks but this error popped out.  What should I do next? 

[BarraHome]

The message is quite clear, you cannot connect to the database. Check your credentials, second if you are using a remote mySQL you might have issues with the connection there (because the timeout).

Is not Prestashop related.

[sajdis]

What permissions should be for index.php? Do I need to check other files for changing permissions?

edit: index.php permissions are 644

Edited October 29, 2019 by sajdis (see edit history)

[BarraHome]

9 minutes ago, sajdis said:

What permissions should be for index.php? Do I need to check other files for changing permissions?

edit: index.php permissions are 644

Please READ my reply, is not an permission error. As i stated before, its a connection issue. https://dev.mysql.com/doc/refman/5.5/en/server-error-reference.html#error_er_lock_wait_timeout

[sajdis]

I'm a quite new working with this. As I understood I need to fix this timeout. I found this:  by innodb_lock_wait_timeout can be set at runtime with the SET GLOBAL or SET SESSION statement. Changing the GLOBAL setting requires privileges sufficient to set global system variables

Could you please tell me how can I fix it? 

[BarraHome]

19 minutes ago, sajdis said:

I'm a quite new working with this. As I understood I need to fix this timeout. I found this:  by innodb_lock_wait_timeout can be set at runtime with the SET GLOBAL or SET SESSION statement. Changing the GLOBAL setting requires privileges sufficient to set global system variables

Could you please tell me how can I fix it? 

You need to speak with your hosting provider, this is not a PS related issue.

Edited October 29, 2019 by BarraHome (see edit history)