diff --git a/synapse/logging/opentracing.py b/synapse/logging/opentracing.py
index d8478c3f67..ae389f3798 100644
--- a/synapse/logging/opentracing.py
+++ b/synapse/logging/opentracing.py
@@ -683,7 +683,7 @@ def get_prometheus_exemplar(
 
     trace_id = getattr(span, "trace_id", None)
 
-    return {"trace_id": trace_id}
+    return {"trace_id": f"{trace_id:x}"}
 
 
 @ensure_active_span("set a tag")
diff --git a/synapse/metrics/_twisted_exposition.py b/synapse/metrics/_twisted_exposition.py
index 0abcd14953..98ed3deb6a 100644
--- a/synapse/metrics/_twisted_exposition.py
+++ b/synapse/metrics/_twisted_exposition.py
@@ -13,7 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from prometheus_client import REGISTRY, CollectorRegistry, generate_latest
+from prometheus_client import REGISTRY, CollectorRegistry
+from prometheus_client.openmetrics.exposition import generate_latest
 
 from twisted.web.resource import Resource
 from twisted.web.server import Request