diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index 0987e931..c6145cd4 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -100,7 +100,7 @@ jobs:
           run: echo "Suffix=-${REF_NAME##*/}" >> $GITHUB_ENV
 
         - name: Generate Suffix
-          if: env.IsTagBuild == 'true'
+          if: env.IsTagBuild != 'true'
           run: echo "Suffix=-nightly.$(date +'%Y%m%d').${{ github.run_number }}" >> $GITHUB_ENV
           
         - name: setup NuGet