diff --git a/go.mod b/go.mod
index 9f0afa63..db175d13 100644
--- a/go.mod
+++ b/go.mod
@@ -22,7 +22,7 @@ require (
 	github.com/stackitcloud/stackit-sdk-go/services/mariadb v0.25.1
 	github.com/stackitcloud/stackit-sdk-go/services/modelserving v0.6.0
 	github.com/stackitcloud/stackit-sdk-go/services/mongodbflex v1.5.2
-	github.com/stackitcloud/stackit-sdk-go/services/objectstorage v1.3.1
+	github.com/stackitcloud/stackit-sdk-go/services/objectstorage v1.4.0
 	github.com/stackitcloud/stackit-sdk-go/services/observability v0.14.0
 	github.com/stackitcloud/stackit-sdk-go/services/opensearch v0.24.1
 	github.com/stackitcloud/stackit-sdk-go/services/postgresflex v1.2.1
@@ -32,7 +32,7 @@ require (
 	github.com/stackitcloud/stackit-sdk-go/services/secretsmanager v0.13.1
 	github.com/stackitcloud/stackit-sdk-go/services/serverbackup v1.3.2
 	github.com/stackitcloud/stackit-sdk-go/services/serverupdate v1.2.1
-	github.com/stackitcloud/stackit-sdk-go/services/serviceaccount v0.11.0
+	github.com/stackitcloud/stackit-sdk-go/services/serviceaccount v0.11.1
 	github.com/stackitcloud/stackit-sdk-go/services/serviceenablement v1.2.2
 	github.com/stackitcloud/stackit-sdk-go/services/ske v1.4.0
 	github.com/stackitcloud/stackit-sdk-go/services/sqlserverflex v1.3.1
diff --git a/go.sum b/go.sum
index 4ba01dd0..dbe08e75 100644
--- a/go.sum
+++ b/go.sum
@@ -174,8 +174,8 @@ github.com/stackitcloud/stackit-sdk-go/services/modelserving v0.6.0 h1:JZI+3sLVA
 github.com/stackitcloud/stackit-sdk-go/services/modelserving v0.6.0/go.mod h1:DvNLTENxoJEQ8AwUvcVBoWqVtdZNS4vEJppTKfvfeec=
 github.com/stackitcloud/stackit-sdk-go/services/mongodbflex v1.5.2 h1:BQ+qAkVS/aGHepE/+gVsvSg1sRkPOyIUI/jkCyUOrWg=
 github.com/stackitcloud/stackit-sdk-go/services/mongodbflex v1.5.2/go.mod h1:oc8Mpwl7O6EZwG0YxfhOzNCJwNQBWK5rFh764OtxoMY=
-github.com/stackitcloud/stackit-sdk-go/services/objectstorage v1.3.1 h1:4jsFLbDVEosYTgQz6lPds1E9KDOiHwjuhWqcG+lo5B4=
-github.com/stackitcloud/stackit-sdk-go/services/objectstorage v1.3.1/go.mod h1:j1SHAS5lN8F9b/iPUOfjAl9QAA9tOT7NKOiDEzcM2zc=
+github.com/stackitcloud/stackit-sdk-go/services/objectstorage v1.4.0 h1:g3yNDUc3JydAikezUrI9bQ4nuMJpVeAQ35jOFfFmq1U=
+github.com/stackitcloud/stackit-sdk-go/services/objectstorage v1.4.0/go.mod h1:foslkEiICdtHR3v0A/i/Rgo6EP9MMula9XNC9luNOgw=
 github.com/stackitcloud/stackit-sdk-go/services/observability v0.14.0 h1:oewwaYjABWbNqDkmSwIXmjDBK4a46+tnznyZSXh3Xk0=
 github.com/stackitcloud/stackit-sdk-go/services/observability v0.14.0/go.mod h1:tJEOi6L0le4yQZPGwalup/PZ13gqs1aCQDqlUs2cYW0=
 github.com/stackitcloud/stackit-sdk-go/services/opensearch v0.24.1 h1:50n87uZn0EvSP9hJGLqd3Wm2hfqbyh7BMGGCk7axgqA=
@@ -194,8 +194,8 @@ github.com/stackitcloud/stackit-sdk-go/services/serverbackup v1.3.2 h1:tfKC4Z6Ua
 github.com/stackitcloud/stackit-sdk-go/services/serverbackup v1.3.2/go.mod h1:wV7/BUV3BCLq5+E1bHXrKKt/eOPVdWgLArWLAq7rZ/U=
 github.com/stackitcloud/stackit-sdk-go/services/serverupdate v1.2.1 h1:hcHX2n5pUsOcv2PPPbSJph1fQ/I6P7g7781T1f1ycEI=
 github.com/stackitcloud/stackit-sdk-go/services/serverupdate v1.2.1/go.mod h1:jZwTg3wU4/UxgNJ7TKlFZ3dTIlnfvppnW8kJTc4UXy8=
-github.com/stackitcloud/stackit-sdk-go/services/serviceaccount v0.11.0 h1:u0PjbKDuIVOMm9hyxLeqSM51ExtJXJ+TdSJT5hDW6wk=
-github.com/stackitcloud/stackit-sdk-go/services/serviceaccount v0.11.0/go.mod h1:QCrAW/Rmf+styT25ke8cUV6hDHpdKNmAY14kkJ3+Fd8=
+github.com/stackitcloud/stackit-sdk-go/services/serviceaccount v0.11.1 h1:crKlHl7QVF97A8CTBK3PBtVpO9c/7qwFvRJi5UN/F7Y=
+github.com/stackitcloud/stackit-sdk-go/services/serviceaccount v0.11.1/go.mod h1:QCrAW/Rmf+styT25ke8cUV6hDHpdKNmAY14kkJ3+Fd8=
 github.com/stackitcloud/stackit-sdk-go/services/serviceenablement v1.2.2 h1:s2iag/Gc4tuQH7x5I0n4mQWVhpfl/cj+SVNAFAB5ck0=
 github.com/stackitcloud/stackit-sdk-go/services/serviceenablement v1.2.2/go.mod h1:DFEamKVoOjm/rjMwzfZK0Zg/hwsSkXOibdA4HcC6swk=
 github.com/stackitcloud/stackit-sdk-go/services/ske v1.4.0 h1:V6RFvybDeJvvmT3g7/BZodF0gozz3TEpahbpiTftbeY=
diff --git a/stackit/internal/services/objectstorage/credential/resource.go b/stackit/internal/services/objectstorage/credential/resource.go
index 3029d6eb..39005dd6 100644
--- a/stackit/internal/services/objectstorage/credential/resource.go
+++ b/stackit/internal/services/objectstorage/credential/resource.go
@@ -496,7 +496,7 @@ func mapFields(credentialResp *objectstorage.CreateAccessKeyResponse, model *Mod
 	} else {
 		// Harmonize the timestamp format
 		// Eg. "2027-01-02T03:04:05.000Z" = "2027-01-02T03:04:05Z"
-		expirationTimestamp, err := time.Parse(time.RFC3339, *credentialResp.Expires)
+		expirationTimestamp, err := time.Parse(time.RFC3339, *credentialResp.Expires.Get())
 		if err != nil {
 			return fmt.Errorf("unable to parse payload expiration timestamp '%v': %w", *credentialResp.Expires, err)
 		}
diff --git a/stackit/internal/services/objectstorage/credential/resource_test.go b/stackit/internal/services/objectstorage/credential/resource_test.go
index 8728922f..24746aa2 100644
--- a/stackit/internal/services/objectstorage/credential/resource_test.go
+++ b/stackit/internal/services/objectstorage/credential/resource_test.go
@@ -61,7 +61,7 @@ func TestMapFields(t *testing.T) {
 			&objectstorage.CreateAccessKeyResponse{
 				AccessKey:       utils.Ptr("key"),
 				DisplayName:     utils.Ptr("name"),
-				Expires:         utils.Ptr(now.Format(time.RFC3339)),
+				Expires:         objectstorage.NewNullableString(utils.Ptr(now.Format(time.RFC3339))),
 				SecretAccessKey: utils.Ptr("secret-key"),
 			},
 			Model{
@@ -100,7 +100,7 @@ func TestMapFields(t *testing.T) {
 		{
 			"expiration_timestamp_with_fractional_seconds",
 			&objectstorage.CreateAccessKeyResponse{
-				Expires: utils.Ptr(now.Format(time.RFC3339Nano)),
+				Expires: objectstorage.NewNullableString(utils.Ptr(now.Format(time.RFC3339Nano))),
 			},
 			Model{
 				Id:                  types.StringValue(id),
@@ -123,7 +123,7 @@ func TestMapFields(t *testing.T) {
 		{
 			"bad_time",
 			&objectstorage.CreateAccessKeyResponse{
-				Expires: utils.Ptr("foo-bar"),
+				Expires: objectstorage.NewNullableString(utils.Ptr("foo-bar")),
 			},
 			Model{},
 			false,