But in the process of bringing it back down and re-checking its software, the company caught yet another issue that could have caused Starliner to collide with its service module when the two separated prior to the capsule’s return to Earth. Teams were able to correct the issue before to the capsule’s return on Dec. 22, but the multitude of problems have led NASA to call for a full re-verification of Boeing’s software — a process that will take analyzing about a million lines of code.