You searched for: “dittograms
dittogram (s) (noun), dittograms (pl)
A letter or a series of letters unintentionally repeated by a writer when reproducing a text: "As a reporter, Jane was under pressure to complete several articles as quickly as possible. Before submitting her work for publication in the newspaper, she saw some dittograms, or written duplications of letters and phrases, and so she corrected them."