diff --git a/test_requirements.txt b/test_requirements.txt
index defb7f848..a87069a3d 100644
--- a/test_requirements.txt
+++ b/test_requirements.txt
@@ -1,5 +1,5 @@
 LunarCalendar>=0.0.9
-ax-platform
+ax-platform==0.2.4
 pystan==2.19.1.1
 fbprophet==0.7.1
 gpytorch