diff --git a/src/Plots.jl b/src/Plots.jl
index 3d499645..971813a3 100644
--- a/src/Plots.jl
+++ b/src/Plots.jl
@@ -20,7 +20,7 @@ function _check_compat(sim::Module)
     be_v = Pkg.Types.read_project(joinpath(Base.pkgdir(sim), "Project.toml")).version
     be_c = _plots_compats[sim_str]
     if be_c isa String # julia 1.6
-        if be_v in Pkg.Types.semver_spec(be_c)
+        if !(be_v in Pkg.Types.semver_spec(be_c))
             @warn "$sim $be_v is not compatible with this version of Plots. The declared compatibility is $(be_c)."
         end
     else