diff --git a/Dockerfile b/Dockerfile
index 5b0b470..3a17051 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 #Setting up basic python and to be root
-FROM python:3.10-slim-buster
+FROM python:3.10-slim
 USER root
 #Setting up system variable
 ENV PETSC_DIR /root/petsc
diff --git a/ngsPETSc/utils/firedrake/hierarchies.py b/ngsPETSc/utils/firedrake/hierarchies.py
index 245954b..14f69c6 100644
--- a/ngsPETSc/utils/firedrake/hierarchies.py
+++ b/ngsPETSc/utils/firedrake/hierarchies.py
@@ -40,7 +40,8 @@ def uniformRefinementRoutine(ngmesh, cdm):
     rdm.removeLabel("pyop2_owned")
     rdm.removeLabel("pyop2_ghost")
     if ngmesh.dim > 2:
-        mapping = MeshMapping(rdm, geo=ngmesh.GetGeometry())
+        sdm = rdm.getRedundant()
+        mapping = MeshMapping(sdm, geo=ngmesh.GetGeometry())
         return (rdm, mapping.ngMesh)
     else:
         #Faster but only works for 2D meshes