Billy (partially found UK children's animated series; 1998-1999)
Billy was an animated TV show created and directed by Vincent James and produced by Fat City Film and The Little Entertainment Group in 1999 that aired from 2000 to 2006 on Nick Jr. in the UK and from the late 2000s to around 2012 on Tiny Pop. According to the TV Tropes, page for Billy, at least 26 episodes were produced
Almost no information exists about Billy, on the internet. It's unknown whether Nick Jr., Tiny Pop, or the creators have it archived.