Fix issues with Yii site - urgent.

We have a site built with the Yii2 framework, that was not built by me, and do not have access to the former developer. The site has recently been migrated to a new server. There are two issues with the site, which we need to have resolved very urgently, One is with a page that is throwing up database connection errors and the other is a problem with search that is not working (not sure but the problem with search could be that it is trying to use sphinx that is missing) This project is very urgent, since we did have someone who said they would be able to fix it but has not managed to do so in the last few days. Please only apply if you have experience with Yii, and if you are comfortable with using somebody else's former code. We don't want to change or rewrite anything, just resolve these two issues.