diff --git a/src/common/counterterm.jl b/src/common/counterterm.jl
index 45353ac..a1cd1aa 100644
--- a/src/common/counterterm.jl
+++ b/src/common/counterterm.jl
@@ -328,11 +328,11 @@ function _inverse(z::AbstractVector{T}) where {T}
         zi[5] = -z[1] .^ 5 + 4z[1] .^ 3 .* z[2] - 3z[1] .* z[2] .^ 2 - 3z[1] .^ 2 .* z[3] + 2z[2] .* z[3] + 2z[1] .* z[4] - z[5]
     end
     if order >= 6
-        zi[6] = z[1] .^ 6 - 5z[1] .^ 4 .* z[2] + 6z[1] .^ 2 .* z[2] .^ 2 + 4z[3] .* z[1] .^ 3
-        -3z[1] .^ 2 .* z[4] - 6z[1] .* z[2] .* z[3] - z[2] .^ 3 + z[3] .^ 2 + 2z[2] .* z[4] + 2z[1] .* z[5] - z[6]
+        zi[6] = z[1] .^ 6 - 5z[1] .^ 4 .* z[2] + 6z[1] .^ 2 .* z[2] .^ 2 + 4z[3] .* z[1] .^ 3 -
+                3z[1] .^ 2 .* z[4] - 6z[1] .* z[2] .* z[3] - z[2] .^ 3 + z[3] .^ 2 + 2z[2] .* z[4] + 2z[1] .* z[5] - z[6]
     end
     if order >= 7
-        error("order must be <= 5")
+        error("order must be <= 6")
     end
     return zi
 end