Please check your edits, you added nodes without valid tags like this one:
node/8743469126

Done.

Thanks for the explanation!
I think the easiest is to delete the objects from this changeset.
Then you can redo the changes on the original objects.

There shouldn't be any issues if you download data either directly in JOSM or via overpass-turbo. They all keep the references to existing objects intact so that no duplicates are created.

Hi,
you added the key 'payment:ep_line' here - is that payment:line_pay? That would be the common key now.

node/4333498892

Hi,
all the objects you added here are duplicates of already existing objects.

This happens to different people every now and then.
Could you explain your workflow? If we can figure out how this happens we might be able to prevent it in the future.

Hi,
could you check these edits? Many buildings got a strange tag:
"viviendas=urba1 area2"
Was it added on purpose? What does it mean?

All the objects in this changeset are duplicates of already existing objects.

This happens to different people every now and then.
Could you explain your workflow? If we can figure out how this happens we might be able to prevent it in the future.

If you use "experimental tagging" please mention it in the changeset comment. Make clear that the tag was intentional and not just a mistake or due to missing knowledge.

Please don't invent new tags - these can not be understood by other mapers (as you can see here). In these cases, please add a description and a fixme yourself. In the best case, you can provide an image of the situation so that others have a clear idea what the situation is exactly.

Nochmal: Ich habe keine Daten gelöscht.
Alle Informationen sind noch unverändert vorhanden.

Ich habe nur undiskutierte, undokumentierte Keys ersetzt durch dokumentierte und weltweit verwendete Keys.
Wenn du/ihr existierende Keys durch neue ersetzen wollt - bitte sucht das Gespräch mit anderen Mappern.

You added the tag 'sign:disabled' here - both parts of this is key are not in use. Traffic signs are tagged using the traffic_sign key, which can take free text as value. Feel free to replace it by an official traffic sign number in case you know it.

Please don't use the main operational OSM database for testing your application! There is a dedicated development server available where you can upload whatever you want.

Hi,
you added at least 4 nodes with only foreign tags like this one:
node/8740886501

Please have a look.

Welcome to OSM!
Please note that all keys you use to identify an object needs to be in English -
everything else is not understood by the software and is not shown on maps.
Please use only tags that are described in the OSM Wiki or are available in the presets of your editor.
This is necessary to make sure that every other user can understand the data.

Bitte schau mal über die ref Tags - die richtige Schreibweise ist
ref:IFOPT, nicht ref:IFOBT

(Sorry, my Italian isn't good enough to write an answer)
As you saw and commented on this morning, this relation has already been added properly (without wrong keys and with members).

Having empty relations in the database is useless - most users are not even able to find and load these to their editor again to edit them properly. As all the data comes from a known source it's easier to recreate the relation.
I don't think leaving a comment on the changeset would have helped - you also tried to reach out to the user a month ago and didn't get a response.

Bitte schau mal nach diesem Knoten, er hat ein merkwürdiges Tag "rased".
node/8736077567

Hi,
what does 'wheelchair:both' mean? Is that about using the sidewalks with a wheelchair? That would be
sidewalk:both:wheelchair=*

What does 'sidewalk=limited' mean? 'limited' is not a commonly used value.

Hi,
could you check the order of parts of your destination keys? The common order is:

destination
[:subkey]
[:to]
[:lanes][:forward|:backward|:both_ways]

e.g. not destination:lanes:ref, but destination:ref:lanes.

Thanks!

Tut mir leid, ich bleibe bei meiner Meinung. Du willst dieses Tagging hier durchsetzen:

"name:etymology:wikidata:missing = de:Anna Schlinkheider (1852-1939), wurde 1919 als erste Frau in den Gemeinderat von Eckamp gewählt"

Der korrekte Key dafür ist aber "name:etymology". So ist es seit 7 Jahren dokumentiert und in Gebrauch. Genau so sind die Daten jetzt auch erfasst.
Möchtest du einen neuen Tag für die gleiche Sache einführen, suche bitte zuerst die Diskussion auf den üblichen Kanälen.

Wenn es unbedingt sein muss, die Information einer fehlenden Wikipedia-Seite in der OSM Datenbank zu vermerken (ich fürchte, da wirst du nicht viel Zustimmung finden), dann wäre soetwas das korrekte Tagging dafür:
name:etymology:wikidata = missing