diff --git a/go.mod b/go.mod
index e205466..20ec3c3 100644
--- a/go.mod
+++ b/go.mod
@@ -5,7 +5,7 @@ go 1.26.2
 require (
 	github.com/codingsince1985/geo-golang v1.9.0
 	github.com/cucumber/godog v0.15.1
-	github.com/ringsaturn/tzf v1.2.0
+	github.com/ringsaturn/tzf v1.2.1
 	github.com/tkuchiki/go-timezone v0.2.3
 )
 
diff --git a/go.sum b/go.sum
index 14d362e..e9553f8 100644
--- a/go.sum
+++ b/go.sum
@@ -37,8 +37,8 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/ringsaturn/go-cities.json v0.6.13 h1:p5afPcJ/tEE6uzFCOzLSHJYXgWnGdPmwZB9KBrEASxc=
 github.com/ringsaturn/go-cities.json v0.6.13/go.mod h1:VtklT4Sod9i6kvXXNZV63sfjeCX9l11OQfaAvPu+p4M=
-github.com/ringsaturn/tzf v1.2.0 h1:lTbQRvBBwhmsfSre74Y9coOYh3g8xDyIJY/10telKms=
-github.com/ringsaturn/tzf v1.2.0/go.mod h1:Umn/OVUgCl96XGHcH1NuKKay2HTBN5xqSiL2Gzsrl2k=
+github.com/ringsaturn/tzf v1.2.1 h1:KAaod68Ey7OSIBfYH+l9/DTKjHnctPUyyAaahaIOn7o=
+github.com/ringsaturn/tzf v1.2.1/go.mod h1:Umn/OVUgCl96XGHcH1NuKKay2HTBN5xqSiL2Gzsrl2k=
 github.com/ringsaturn/tzf-dist v0.0.2026-b-fix1 h1:2XqoK1ymoselNxhSVWTC8SwfBaleLWrd+Wf1mlz/f9Q=
 github.com/ringsaturn/tzf-dist v0.0.2026-b-fix1/go.mod h1:MLn3mRLioai5ceZLV8k+uAr4cLxdVEHoTQIGKpuVS/c=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=