Authentication Failure 5GMM Cause: Synch Failure

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Is this expected behavior? Or some kind of bug or missing configuration?
When I’m registering the UE for the first time, I get this error and warnings:

[INFO][UDM][UEAU] Handle GenerateAuthDataRequest
[ERRO][UDM][UEAU] opStr length is 0
[INFO][UDR][DRepo] Handle ModifyAuthentication
[INFO][UDR][GIN] | 204 | | PATCH | /nudr-dr/v1/subscription-data/imsi-208930000000003/authentication-data/authentication-subscription |
[INFO][UDM][GIN] | 200 | | POST | /nudm-ueau/v1/suci-0-208-93-0000-0-0-0000000003/security-information/generate-auth-data |
[INFO][AUSF][UeAuthPost] Add SuciSupiPair (suci-0-208-93-0000-0-0-0000000003, imsi-208930000000003) to map.
[INFO][AUSF][UeAuthPost] Use 5G AKA auth method
[INFO][AUSF][5gAkaAuth] XresStar = 6262393230326464616239343565393034666663306130616234363434633939
[INFO][AUSF][GIN] | 201 | | POST | /nausf-auth/v1/ue-authentications |
[INFO][AMF][GMM][AMF_UE_NGAP_ID:1] Send Authentication Request
[INFO][AMF][NGAP][][AMF_UE_NGAP_ID:1] Send Downlink Nas Transport
[INFO][AMF][NGAP][][AMF_UE_NGAP_ID:1] Uplink NAS Transport (RAN UE NGAP ID: 1)
[INFO][LIB][FSM] Handle event[Gmm Message], transition from [Authentication] to [Authentication]
[INFO][AMF][GMM][AMF_UE_NGAP_ID:1] Handle Authentication Failure
[WARN][AMF][GMM][AMF_UE_NGAP_ID:1] Authentication Failure 5GMM Cause: Synch Failure
[INFO][AUSF][UeAuthPost] HandleUeAuthPostRequest
[INFO][AUSF][UeAuthPost] Serving network authorized
[WARN][AUSF][UeAuthPost] Auts: 0ec3d15a43e597cb69613901b766
[WARN][AUSF][UeAuthPost] imsi-208930000000003
[WARN][AUSF][UeAuthPost] b074885271e11f1a39a1ccba963e95cb
[WARN][AUSF][UeAuthPost] Rand: b074885271e11f1a39a1ccba963e95cb

UERANSIM logs this message:
[2022-09-04 20:33:44.133] [nas] [debug] Sending Authentication Failure due to SQN out of range

After these messages, everything seems to be okay, UE registers and gets a PDU session.
But still, I’m wondering if this should happen.

free5gc 3.2.1