Anti-Ahmadis often quote a reference of Hadrat Masih Maud (as) which says Allah leaves me not on error even for the blink of an eye:
This is taken out of context and he (as) is speaking specifically regarding his Qur’anic tafsir. This has nothing to do with prophecies or general mistakes of forgetfulness and sahw (in writing). The same page says : “I do not claim to be free from forgetfulness and mistakes of writing”