Hello. We have an issue with REGISTER to Provider. When Provider answers 401 Kamailio don't send any REGISTER with digest auth

IP ourservice.com.5068 > provider.dev.5060: UDP, length 468
E...U...@.3'
..............AREGISTER sip:provider.dev SIP/2.0
Via: SIP/2.0/UDP ourservice.com:5068;branch=z9hG4bK4238.45a4a626000000000000000000000000.0
To: <sip:login@provider.dev>
From: <sip:login@provider.dev>;tag=6a39af2190f8b2c99cc63bfeb3a3959c-1ff8
CSeq: 10 REGISTER
Call-ID: 1b3f9f5d5822eca2-16804@ourservice.com
Max-Forwards: 70
Content-Length: 0
User-Agent: kamailio (4.3.0-dev5 (x86_64/linux))
Contact: <sip:login@ourservice.com:5068>
Expires: 360


IP provider.dev.5060 > ourservice.com.5068: UDP, length 572
E..XC...-.W.....
........DkJSIP/2.0 401 Unauthorized
Via: SIP/2.0/UDP ourservice.com:5068;branch=z9hG4bK4238.45a4a626000000000000000000000000.0;received=23.100.24.250
From: <sip:login@provider.dev>;tag=6a39af2190f8b2c99cc63bfeb3a3959c-1ff8
To: <sip:login@provider.dev>;tag=as6ad61d4a
Call-ID: 1b3f9f5d5822eca2-16804@ourservice.com
CSeq: 10 REGISTER
Server: FastTel SoftSwitch
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH
Supported: replaces
WWW-Authenticate: Digest algorithm=MD5, realm="provider.dev", nonce="63fc6951"
Content-Length: 0