diff --git a/api/auth/center.go b/api/auth/center.go
index f9099517..3dccb295 100644
--- a/api/auth/center.go
+++ b/api/auth/center.go
@@ -20,7 +20,8 @@ import (
 	"go.uber.org/zap"
 )
 
-var authorizationFieldRegexp = regexp.MustCompile(`AWS4-HMAC-SHA256 Credential=(?P<access_key_id_cid>[^/]+)_(?P<access_key_id_oid>[^/]+)/(?P<date>[^/]+)/(?P<region>[^/]*)/(?P<service>[^/]+)/aws4_request,\s*SignedHeaders=(?P<signed_header_fields>.+),\s*Signature=(?P<v4_signature>.+)`)
+// authorizationFieldRegexp -- is regexp for credentials with Base58 encoded cid and oid and '0' (zero) as delimiter.
+var authorizationFieldRegexp = regexp.MustCompile(`AWS4-HMAC-SHA256 Credential=(?P<access_key_id_cid>[^/]+)0(?P<access_key_id_oid>[^/]+)/(?P<date>[^/]+)/(?P<region>[^/]*)/(?P<service>[^/]+)/aws4_request,\s*SignedHeaders=(?P<signed_header_fields>.+),\s*Signature=(?P<v4_signature>.+)`)
 
 type (
 	// Center is a user authentication interface.
@@ -89,7 +90,7 @@ func (c *center) Authenticate(r *http.Request) (*accessbox.GateData, error) {
 		return nil, fmt.Errorf("failed to parse x-amz-date header field: %w", err)
 	}
 
-	accessKeyID := fmt.Sprintf("%s_%s", sms1["access_key_id_cid"], sms1["access_key_id_oid"])
+	accessKeyID := fmt.Sprintf("%s0%s", sms1["access_key_id_cid"], sms1["access_key_id_oid"])
 	accessKeyAddress := fmt.Sprintf("%s/%s", sms1["access_key_id_cid"], sms1["access_key_id_oid"])
 
 	address := object.NewAddress()
diff --git a/authmate/authmate.go b/authmate/authmate.go
index 58ab058f..510caacd 100644
--- a/authmate/authmate.go
+++ b/authmate/authmate.go
@@ -179,7 +179,7 @@ func (a *Agent) IssueSecret(ctx context.Context, w io.Writer, options *IssueSecr
 		return fmt.Errorf("failed to put bearer token: %w", err)
 	}
 
-	accessKeyID := address.ContainerID().String() + "_" + address.ObjectID().String()
+	accessKeyID := address.ContainerID().String() + "0" + address.ObjectID().String()
 
 	ir := &issuingResult{
 		AccessKeyID:     accessKeyID,