diff --git a/coap/client.go b/coap/client.go
index fc3efb4d5c..6b278ce0ff 100644
--- a/coap/client.go
+++ b/coap/client.go
@@ -62,6 +62,7 @@ func (c *client) Cancel() error {
 	if err := c.conn.WriteMessage(pm); err != nil {
 		c.logger.Error(fmt.Sprintf("Error sending message: %s.", err))
 	}
+	c.conn.ReleaseMessage(pm)
 	return c.conn.Close()
 }
 
diff --git a/go.sum b/go.sum
index 456e88b2e3..76676bc09d 100644
--- a/go.sum
+++ b/go.sum
@@ -45,7 +45,6 @@ github.com/caarlos0/env/v10 v10.0.0 h1:yIHUBZGsyqCnpTkbjk8asUlx6RFhhEs+h7TOBdgdz
 github.com/caarlos0/env/v10 v10.0.0/go.mod h1:ZfulV76NvVPw3tm591U4SwL3Xx9ldzBP9aGxzeN7G18=
 github.com/caarlos0/env/v11 v11.0.0 h1:ZIlkOjuL3xoZS0kmUJlF74j2Qj8GMOq3CDLX/Viak8Q=
 github.com/caarlos0/env/v11 v11.0.0/go.mod h1:2RC3HQu8BQqtEK3V4iHPxj0jOdWdbPpWJ6pOueeU1xM=
-github.com/cenkalti/backoff v2.2.1+incompatible/go.mod h1:90ReRw6GdpyfrHakVjL/QHaoyV4aDUVVkXQJJJ3NXXM=
 github.com/cenkalti/backoff/v3 v3.0.0/go.mod h1:cIeZDE3IrqwwJl6VUwCN6trj1oXrTS4rc0ij+ULvLYs=
 github.com/cenkalti/backoff/v3 v3.2.2 h1:cfUAAO3yvKMYKPrvhDuHSwQnhZNk/RMHKdZqKTxfm6M=
 github.com/cenkalti/backoff/v3 v3.2.2/go.mod h1:cIeZDE3IrqwwJl6VUwCN6trj1oXrTS4rc0ij+ULvLYs=
@@ -708,12 +707,6 @@ google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8
 google.golang.org/grpc v1.29.1/go.mod h1:itym6AZVZYACWQqET3MqgPpjcuV5QH3BxFS3IjizoKk=
 google.golang.org/grpc v1.63.2 h1:MUeiw1B2maTVZthpU5xvASfTh3LDbxHd6IJ6QQVU+xM=
 google.golang.org/grpc v1.63.2/go.mod h1:WAX/8DgncnokcFUldAxq7GeB5DXHDbMF+lLvDomNkRA=
-google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
-google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
-google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
-google.golang.org/protobuf v1.20.1-0.20200309200217-e05f789c0967/go.mod h1:A+miEFZTKqfCUM6K7xSMQL9OKL/b6hQv+e19PK+JZNE=
-google.golang.org/protobuf v1.21.0/go.mod h1:47Nbq4nVaFHyn7ilMalzfO3qCViNmqZ2kzikPIcrTAo=
-google.golang.org/protobuf v1.22.0/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2l/sGQquU=
 google.golang.org/protobuf v1.34.1 h1:9ddQBjfCyZPOHPUiPxpYESBLc+T8P3E+Vo4IbKZgFWg=
 google.golang.org/protobuf v1.34.1/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc h1:2gGKlE2+asNV9m7xrywl36YYNnBG5ZQ0r/BOOxqPpmk=