How can I delete an extra or doubled entry (e.g. research article, book) from my research list? Occasionally, one or more entries have been repeatedly added and uploaded.
See the section "Why are there duplicate research items on my profile?" in the help page https://help.researchgate.net/hc/en-us/articles/14293081125777-Reviewing-editing-and-featuring-your-research to get instructions how to merge two entries.