The Formula 2019 one on netflix

Film version of the 2017 miniseries. After discovering the elixir of youth a scientist reunites with her high school sweetheart, bringing back many dilemmas from the past. She tests the formula on herself and each dose makes her 30 years younger. She then starts switching between her current persona and the younger one, becoming her own rival. Meanwhile, her former boyfriend falls in love with both versions of the scientist, unaware this love triangle includes both identities of the same woman.