SEO company raising issues with site

[ConnectCreative]

I've completed a site for a client. They are now using an SEO company to manage the site who have raised the following issues, most of which I'm at a loss to understand.

Site is Undercarriage and Ground Engaging Tool specialist - ITS Trac

Issues raised are:

1. Is there any reason the html file size of the site is so large? As it is causing the code/text ratio to be distorted and also effecting the load and response time of the mobile version of the site.
2. Also can you please have a look at the H tags within the site as they all seem to be named irrelevantly and there are a lot of images that have no title or alt tag?
3. Also the tool is flagging up some basic html errors in some of the pages.
4. It is also finding multiple mobile versions of the site, is there any reason for this and if so has the correct canonical tag been put in place on each version?

Any help on these issues would be greatly appreciated.

Neil.

[Mylenium]

You have to hand-optimize the code by editing the native HTML. There is no magic "clean up your own mess" button in Muse, which is what it comes down to: Due to how Muse works, the code will always be bloated and have SEO issues.

Mylenium