I have a problem with, I think, simple API query: https://pl.wikipedia.org/w/api.php?maxlag=10&action=query&list=usercontribs&ucuser=Pawe%C5%82_Ziemian_BOT&uclimit=10&ucprop=title|timestamp|comment&format=json
The same query with other username works fine: https://pl.wikipedia.org/w/api.php?maxlag=10&action=query&list=usercontribs&ucuser=Pawe%C5%82_Ziemian&uclimit=10&ucprop=title|timestamp|comment&format=json (for similar username and https://pl.wikipedia.org/w/api.php?maxlag=10&action=query&list=usercontribs&ucuser=MalarzBOT&uclimit=10&ucprop=title|timestamp|comment&format=json (for other bot)
The query was working fine for all users till November 2018. Few days ago I found, that this query is not working now.