Site not indexing in Google. Sitemap submission to S.C. triggering error and redirecting improperly

[thawley]

Hello
A few problems going on with a site: https://www.24hrtowingoceansideca.com/ as it is not showing pages being indexed in search console. Submitted the sitemap several different times. Ran fetch as google several times, yet in search console it's showing:
- 0 indexed URLs

- Sitemap triggering error message:
sitemap could not be read

General HTTP error
We encountered an error while trying to access your Sitemap. Please ensure your Sitemap follows our guidelines and can be accessed at the location you provided and then resubmit.

** EDIT ** Resubmitted sitemap again and now giving error:
"sitemap is HTML
Your Sitemap appears to be an HTML page. Please use a supported sitemap format instead."

Here's what robot.txt has:

Sitemap: https://www.24hrtowingoceansideca.com/sitemap.xml

User-agent: NerdyBot
Disallow: /

User-agent: *
Disallow: /ajax/
Disallow: /apps/
Disallow: /city.html 

No idea what's going on any assistance would be much appreciated!

[ACn1]

Hi.

Can't get too involved but a quick check says your pages have been indexed.

Test this. In Google browser type: "site:24hrtowingoceansideca.com/ "

It will bring up the pages indexed. And they look a little confusing especially if you check the different urls. Most omit "https". This si a possible place to start from.

The sitemap.xml does work if everything is inplace and consistent.

Good luck.

(Also noticed 2 verification codes in the header- so double check the site is verified, and no confusion exists.)

[thawley]

Yes we just added SSL, so the pages you're seeing w/o https showing were simply indexed prior and haven't updated yet (which they should have by now but guessing this sitemap issue has something to do with it, even though Google should be crawling the links on the pages anyway) 

Our main issue is rankings drop from positions around top 3 to 70-80 (to literally off the map). SSL switch will certainly drop rankings for a bit but never seen anything like this. 

And search console still showing that sitemap cannot be read which is simiply baffling. Resubmitted many times. Unpublished then republished the site and tried again..

My partner on the site said there was a temp DNS error where front page was showing 404 error but has since been resolved for over a week. I'm wondering if Google crawled the site at that time and found that error, then deindexed the homepage thus the rankings drop. Since then I've resubmitted homepage for indexing and it has been re-indexed, but the other pages aren't updating in index properly after request google bot fetch over a week ago. 

Have another site that's similar to this one - also just updated SSL on it, and it works great and didn't lose any rankings and its sitemap is being found successfully. Considering switching the site over to wordpress since will have more control over the sitemap.