Radio Failure in Radio ITF process

Hello.
May you assist me with this cause found on a ZTE site from USN trace it called Radio Failure in Radio ITF process.

usn-mm-s1ap-cause-radio-nw-fail-in-radio-itf-proc

Was curious what itf meant - bit of googling, it means interface.

My suggestion: This issue could be related to reestablishing failure or handover-failure during call setup phase etc.