diff --git a/go.mod b/go.mod
index a531c5c..e30ecb0 100644
--- a/go.mod
+++ b/go.mod
@@ -7,7 +7,7 @@ require (
 	github.com/domodwyer/mailyak v3.1.1+incompatible
 	github.com/mattbaird/gochimp v0.0.0-20200820164431-f1082bcdf63f
 	github.com/mrz1836/go-ses v0.3.2
-	github.com/mrz1836/postmark v1.6.4
+	github.com/mrz1836/postmark v1.6.5
 )
 
 require (
diff --git a/go.sum b/go.sum
index 28c52c0..94ec971 100644
--- a/go.sum
+++ b/go.sum
@@ -20,8 +20,8 @@ github.com/mattbaird/gochimp v0.0.0-20200820164431-f1082bcdf63f h1:Sbn1gG/7kAsH2
 github.com/mattbaird/gochimp v0.0.0-20200820164431-f1082bcdf63f/go.mod h1:UaYd2gciRA1AoYEN6S+EiSNFK/0XHj9e1Wgloicgh6s=
 github.com/mrz1836/go-ses v0.3.2 h1:eN2zu8WYRqXMNctboA4Zaj7tDe/N+bdTIunBD5oAIu0=
 github.com/mrz1836/go-ses v0.3.2/go.mod h1:BMnzf1aACzkrQz27BTMYgWNLf9P8WzF0QJB/7snMGw0=
-github.com/mrz1836/postmark v1.6.4 h1:x5g0zjFE1q1wOgZ3N22rtGMyfKd3GBo4O874cAUw6bQ=
-github.com/mrz1836/postmark v1.6.4/go.mod h1:6z5MxAH00Kj44owtQaryv9Pbqp5OKT3wWcRSydB0p0A=
+github.com/mrz1836/postmark v1.6.5 h1:FSlysQmx9n4NnU4IsvZ0nN+rylNqPHvqYcHtuSk9yi8=
+github.com/mrz1836/postmark v1.6.5/go.mod h1:6z5MxAH00Kj44owtQaryv9Pbqp5OKT3wWcRSydB0p0A=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=