diff --git a/NDTensors/src/lib/GradedAxes/src/abstractgradedunitrange.jl b/NDTensors/src/lib/GradedAxes/src/abstractgradedunitrange.jl
index 1953230045..8782ddfd61 100644
--- a/NDTensors/src/lib/GradedAxes/src/abstractgradedunitrange.jl
+++ b/NDTensors/src/lib/GradedAxes/src/abstractgradedunitrange.jl
@@ -81,7 +81,7 @@ function tensor_product(
       return fuse(isdual ? dual(l1) : l1, isdual ? dual(l2) : l2)
     end,
   )
-  return gradedrange(a, nondual_sectors_a, isdual)
+  return gradedrange(nondual_sectors_a, a, isdual)
 end
 
 function Base.show(io::IO, mimetype::MIME"text/plain", a::AbstractGradedUnitRange)
diff --git a/NDTensors/src/lib/GradedAxes/src/gradedunitrange.jl b/NDTensors/src/lib/GradedAxes/src/gradedunitrange.jl
index 8c6cb30535..ef0cc528c6 100644
--- a/NDTensors/src/lib/GradedAxes/src/gradedunitrange.jl
+++ b/NDTensors/src/lib/GradedAxes/src/gradedunitrange.jl
@@ -22,9 +22,9 @@ function gradedrange(sectors_lengths::Vector{<:Pair{<:Any,Int}}, isdual=false)
   return gradedrange(first.(sectors_lengths), last.(sectors_lengths), isdual)
 end
 
-function gradedrange(a::BlockedUnitRange, nondual_sectors::Vector, isdual=false)
-  if length(nondual_sectors) != length(blocks(a))
-    throw(DomainError("BlockedUnitRange and sectors lengths do not match"))
+function gradedrange(nondual_sectors::Vector, a::BlockedUnitRange, isdual=false)
+  if length(nondual_sectors) != length(blocks(a)) != length(nondual_sectors)
+    throw(DomainError("Number of sectors and number of blocks do not match"))
   end
   return GradedUnitRange(a, nondual_sectors, isdual)
 end