diff --git a/Project.toml b/Project.toml
index 4e4d7d0..9ef2b72 100644
--- a/Project.toml
+++ b/Project.toml
@@ -24,7 +24,7 @@ ChainRules = "1"
 ChainRulesCore = "1"
 JLD2 = "0.5"
 KrylovKit = "0.9.2"
-OptimKit = "0.3-0.4"
+OptimKit = "0.3,0.4"
 Revise = "3"
 TensorKit = "0.14.3"
 TensorKitManifolds = "0.7"