It is not uncommon for those mounting clamps to wear a hole in the line. The plastic or rubber cushions give way and then there is metal-to-metal contact. If you need to drive the car a limited amount (ie: to get home) before making a permanent repair, I would suggest splitting a short piece of fuel hose, then clamping if over the hole with a small hose clamp. That should at least slow the leak to an acceptable level, if it does not stop it completely. Then monitor the ATF level closely.