Good day,
I've plenty experience on cybersecurityworking with Joomla websites and other CMS.
Let me know the error you are getting and i will tell you how we can work it out and date line, honestly my guess is that it can be done in one day, actually in a couple of hours.
I've worked in a web hosting company for over 18 years as Tech Support Level 3 under windows and linux enviroments and different code languages like php, .net, js, etc.
Feel free to contact me to discuss further details.
Best regards.