Does lifting the feet off the ground during prostration invalidate the prayer?

For the prostration (sujood) to be valid and complete, at least one toe of the feet must touch the ground for the duration it takes to say "Subhānallāhi’l-‘azīm".

If none of the toes touch the ground for this period, the prostration is not valid, and thus the prayer is also not valid. (Aliyyü’l-Qārī, Fathu bābi’l-‘ināyah, 1/251; Shurunbulālī, Marāqī al-falāh, 87) If the feet have touched the ground sufficiently for the prostration to be valid, lifting them off the ground beyond this does not invalidate the prayer.

Source: T.C. Diyanet İşleri Başkanlığı, Din İşleri Yüksek Kurulu