This will happen, since an anime episode adapts from 2 to 4 chapters of the
manga, making the story get closer and for that reason they stop the broadcast
of the anime so that the manga advances even more or broadcast it by dividing
it into seasons, for this reason I show you the
continuation in manga of the anime the seven deadly sins.
If you want to follow the anime, you should know the the seven deadly sins manga chapter after anime or what chapter in manga is the last episode of nanatsu no taizai. The anime is currently airing on the television channel JNN (MBS, TBS) by A-1 Pictures Studio, the last canon episode that aired is 24 of the third season, which corresponds to manga 265 and 266.
Episode 24 of the 3rd season = Manga 265 and 266
So if you want to read the seven deadly sins manga after anime, you should start reading from chapter 266 (Page 15) of the manga. If you want to see the list of episodes as well as the filler that contains this series, here is the article Nanatsu no Taizai Chronological Order, which also shows you the order to follow the series.
Manga chapter 266 corresponds to volume 32 of nanatsu no taizai. This
volume contains the following chapters:
259. Britannia devastada por la guerra
260. Cosas que quiero decirte
261. Un gato perdido
262. Aquel retorcido por la oscuridad
263. Ráfaga de Oscuridad
264. Un deformado, retorcido, hombre destrozado
265. Un alborotado amor
266. El Seguidor y el Seguido