3GPP 24.501 v20.0.0 — the document's own text
5.5.2.2.2 UE-initiated de-registration procedure completion
Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).
When the DEREGISTRATION REQUEST message is received by the AMF, the AMF shall send a DEREGISTRATION ACCEPT message to the UE, if the De-registration type IE does not indicate "switch off". Otherwise, the procedure is completed when the AMF receives the DEREGISTRATION REQUEST message.
The UE, when receiving the DEREGISTRATION ACCEPT message, shall stop timer T3521, stop timer T3519 if running, and delete any stored SUCI.