If there are too many candidate moves that the baby can learn, they follow this precedent, with each new move overwriting previous ones: ... 4. **Any egg moves known by either parent (or the father only in Gen 2-5).**
Since you mentioned that your Togepi lost Extrasensory, it does not know the move anymore and cannot pass it down to its offspring. To get another Togepi with Extrasensory, you have to breed a female Togetic/Togekiss with a male Pokemon that knows Extrasensory. The easiest way to do this is with a Hoothoot or Noctowl, since Hoothoot learns Extrasensory at level 37 and Noctowl learns it at level 42.