diff --git a/sumpy/layerpot.py b/sumpy/layerpot.py
index cb0c5d3c623289420483368b02774a6101a7d288..a73d6ab5b591e6a3a42bd4103325d245e5b4a800 100644
--- a/sumpy/layerpot.py
+++ b/sumpy/layerpot.py
@@ -158,7 +158,7 @@ class LayerPotentialBase(KernelComputation):
         for expn in self.expansions:
             loopy_knl = expn.prepare_loopy_kernel(loopy_knl)
 
-        loopy_knl = lp.tag_data_axis(loopy_knl, "center", 0, "sep")
+        loopy_knl = lp.tag_data_axes(loopy_knl, "center", "sep,C")
 
         return loopy_knl