Likewise relation/957520 and relation/957519 have been assigned the same wikidata ID. In this case should they perhaps share one relation that has the same wikidata ID?

Hello,
I think that something has gone wrong here. You've set the wikidata ID of both relation/195384 and relation/88077 to https://www.wikidata.org/wiki/Q23098 .
They're different entities on the ground. Can you explain how you actually did the matching, and what you're actually trying to do here?
Best Regards,
Andy

OK - thanks. That makes sense.

Hello and welcome to OpenStreetMap!
You've deleted a lot of trails in this edit - was that deliberate or by accident? If it was accidental, don't worry - we can restore them, just let people know.
Oh, and any other questions, please don't hesitate to ask.
Best Regards,
Andy

Hello and welcome to OpenStreetMap!
I think that something went wrong with way/454053579 - did you start drawing a line and not figure out how to stop?
I suspect it might be best if we undo this change altogether and let you start again - does that sound OK to you?
Best Regards,
Andy

Oops! You've just moved the library node/4505868690/history to the middle of the Atlantic Ocean!
I'm guessing that the app that you used was https://itunes.apple.com/us/app/wemapp-social/id1163187675?mt=8 - do you know the "Giovanni Albano" who wrote it?
Best Regards,
Andy

Hello,
I've changed this back in changeset/43742170 . The reason why was because names in Sardinia had been subject to a "tit for tat" series of changes (which you can see from the high version numbers of the objects in this changeset). In
https://lists.openstreetmap.org/pipermail/talk-it/2016-September/054885.html I explained that further changes would be changed back, and the names kept as they were while the discussion continues.
This is your first edit to OpenStreetMap, so please don't be disheartened - there are lots of things that you can add to the map, both in Sardinia and beyond.
Best Regards,
Andy Townsend, on behalf of OpenStreetMap's Data Working Group.

Is node/2313145352 perhaps a duplicate of the Pharmacy to the west?

There have been many changeset discussions in the past about your editing of the path of the former Berlin Wall changeset/43577513 . In OpenStreetMap we edit things as they exist now, not as they used to exist or how we might like them to exist.
Please don't make further "fantasy edits" like this; if you do you may be blocked from editing OpenStreetMap.
Best Regards,
Andy Townsend, on behalf of OpenStreetMap's Data Working Group.

Grr. The 55a doesn't go through Clay Cross. Will need to correct...

"Hello,
Please don't add test data to the live OpenStreetMap Server. If you want a test server, perhaps http://api06.dev.openstreetmap.org/ would work for you?
Best Regards,
Andy

Thanks - hopefully someone local will comment.

It used to match the old "Dayrider" area, and the old "Plusbus" zone which was based on that. When the Dayrider area was made smaller and Dayrider+ introduced, the Plusbus zone was reduced to match the smaller Dayrider area, so this area matched none of the public transport areas around Chesterfield.
See list discussion at https://lists.openstreetmap.org/pipermail/talk-gb/2016-November/thread.html#19452 .

Thanks - I've merged the various "Sea Life Centre" features together. Most of the details are on a node that's tagged "tourism=aquarium".

Hello and welcome to OpenStreetMap!
If the Henry Peacock has actually been demolished, you can delete it. You won't be able to use MAPS.ME to do that though - you can use one of the a PC-based in-browser editors.
Best Regards,
Andy

Hello,
You've added way/351237387 as a landuse=forest, but has the name of a reservoir. What is it really?
Cheers,
Andy

If it still exists in the imagery, and there's been no reply, I'd restore it and add a note in case anyone local can add any more information.

Hello,
Please don't use the live OpenStreetMap Server for testing. If you want a test server, perhaps http://api06.dev.openstreetmap.org/ would work for you?
Best Regards,
Andy

Hello and welcome to OpenStreetMap!
You may not be aware, but when you edit OpenStreetMap you're editing a map that everyone can see, not just your personal copy. Please do continue editing, but please do only add things that are verifiable on the ground. If you want to add a personal bookmark to MAPS.ME you can - just select the thing that you want to bookmark and select "menu" and then "bookmark".
Please don't add things that don't exist, or other "test data". If you've got any question please email data@osmfoundation.org .
Best Regards,
Andy Townsend, on behalf of OpenStreetMap's Data Working Group

Hello and welcome to OpenStreetMap!
Is "Emma's House" really a tourist attraction?
Best Regards,
Andy