Electric Light Orchestra evolved from The Move, who first charted in 1972 with Do Ya. A new version of the song became a #24 hit in March 1977.
Badfinger – whose 1970s hits include Baby Blue, No Matter What, Day After Day and Come & Get It – first charted in 1969 with Maybe Tomorrow. They were then known as the Iveys.
The Moments – Harry Ray, Al Goodman, Billy Brown –had several 1970s hits including Love On A Two Way Street, I Do, Sexy Mama and Gotta Find A Way. In February 1980, they had a number-one R&B hit and #5 pop hit with Special Lady – under the name of Ray, Goodman & Brown.
Google's A.I. says, "'One-hit wonder' refers to a musical artist or group that achieves widespread popularity and recognition for a single hit song but fails to sustain that level of success with subsequent releases. While they may have other songs, these are not as widely known or successful as their one prominent hit." I would define "one-hit wonder" as an artist or group who had a top-ten hit but no other songs in the top 40.