diff --git a/src/notary.py b/src/notary.py
index ea57e78..2fd23f1 100644
--- a/src/notary.py
+++ b/src/notary.py
@@ -88,8 +88,7 @@ class DeleteCertificateRequestResponse:
 class CreateCertificateParams:
     """Parameters to create a certificate in Notary."""
 
-    csr: str
-    cert_chain: list[str]
+    certificate: str
 
 
 @dataclass
@@ -263,7 +262,7 @@ def create_certificate(
         if len(csr_ids) != 1:
             logger.error("given CSR not found in Notary")
             return None
-        create_certificate_params = CreateCertificateParams(csr=csr, cert_chain=cert_chain)
+        create_certificate_params = CreateCertificateParams(certificate="\n".join(cert_chain))
         response = self._make_request(
             "POST",
             f"/api/{self.API_VERSION}/certificate_requests/{csr_ids[0].id}/certificate",
diff --git a/tests/integration/test_charm.py b/tests/integration/test_charm.py
index 51e9665..e56d9e8 100644
--- a/tests/integration/test_charm.py
+++ b/tests/integration/test_charm.py
@@ -49,13 +49,11 @@ async def test_build_and_deploy(ops_test: OpsTest, request: pytest.FixtureReques
         "self-signed-certificates",
         application_name=TLS_PROVIDER_APPLICATION_NAME,
         channel="edge",
-        trust=True,
     )
     await ops_test.model.deploy(
         "tls-certificates-requirer",
         application_name=TLS_REQUIRER_APPLICATION_NAME,
         channel="edge",
-        trust=True,
     )
     await ops_test.model.deploy(
         "prometheus-k8s",