I've never forgotten to take my phone to school with me, but I have forgotten my computer at home several times.
ーI've never forgotten to take my phone to school with me, but I have forgotten my computer at home several times.
「スマホを学校に持っていくのを忘れたことはないが、何回か家にパソコンを忘れたことはある」
I've never forgotten to take my phone to school with me. で「スマホを学校に持っていくのを忘れたことはない」
I have forgotten my computer at home. で「パソコンを家に忘れたことがある」
ご参考まで！
カナダ 
