I regullary run bot for creating new items on cs.wikisource.
pwb.py newitem1 -start:! -family:wikisource -subpage:0 -lastedit:0 -pageage:7

Today bot creates about 3500 new items, but (almost) all are duplicates

https://www.wikidata.org/w/index.php?title=Special:Contributions&offset=20200407235959&limit=500&target=JAnDbot&namespace=all&tagfilter=&start=2020-04-07&end=2020-04-07

eg https://www.wikidata.org/wiki/Q19534528 vs https://www.wikidata.org/wiki/Q89651128

I don't understand how is it possible to create item with same sitelink.