On submitting it to google, we get a "couldn't fetch" error. No information is provided as to the cause.

I have run several tests, and can confirm the sitemap is not blocked by robots.txt. It also allows crawling by googlebot. As required, we have made a new property in Google Console for the HTTPS version of the forum.
We have also searched this help forum on the matter, and found a suggestion to add an extra "/" which did not work.

Any assistance would be appreciated.

Thanks.
(we use phpBB2)

I have the same issue, it shows my sitemap as couldn't be fetched, but reading this

Couldn't fetch sitemap

I see that google is able to fetch my url. To get further help I think you will have to contact Google. My site is showing up in their search engine, so I am not to concerned by this glitch.

In the link I have given it tells you how to check if your url is posing any problems with Google. If it isn't like me, then the not fetched just means it is still pending. My latest attempt was on the 12th of June and it still shows as couldn't fetch. I don't know if this is the permanent state of display with this problem on Googles side. However I now have pages indexed.

Either way you will have to contact Google if you want help with it.

Thanks very much Anji 1.

I, too, have pages indexed. I have used the inspection tool before, which showed that the sitemap URL is indexed by google, as forumotion allows that. It thereby also gets "fetched."

It's just not fetched when submitted as a sitemap.

You're welcome @Richardr

To be honest I am quite annoyed that this is a known problem, yet google still have not fixed it. I may contact them to complain about it

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