3GPP 24.501 v20.0.0 — the document's own text
8.3.3.6 Re-attempt indicator
Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).
The network may include this IE if the network includes the Back-off timer value IE and the 5GSM cause value is not #26 "insufficient resources", #28 "unknown PDU session type", #39 "reactivation requested", #46 "out of LADN service area", #54 "PDU session does not exist", #67 "insufficient resources for specific slice and DNN", #68 "not supported SSC mode", or #69 "insufficient resources for specific slice".