Hello Sir,
We will fix your problem, it is related to security and php code and some server settings. if you have SSH access please provide it with all WP sites FTP.
I have gone through your requirements is Problema en Servidor dedicado Linux CentOS.
we brief and understand your idea and preference for job as you are looking for.
I have more than 5+ years of experience in PHP, Wordpress, Magento. I have developed more than 50 websites.
Please see our feedback and review.
Please send me message for further conversation.
Thanks,
Arity Infoway