diff --git a/auth-helper/src/jwt.rs b/auth-helper/src/jwt.rs
index 5fd049f..e9ce8af 100644
--- a/auth-helper/src/jwt.rs
+++ b/auth-helper/src/jwt.rs
@@ -140,13 +140,12 @@ impl ClaimsBuilder {
         let mut claims = Claims::new(self.iss, self.sub, self.aud, now);
 
         if let Some(exp) = self.exp {
-            claims.exp = now
-                .checked_add(exp)
-                .ok_or_else(|| Error::InvalidExpiry {
-                    issued_at: now,
-                    expiry: exp,
-                })
-                .map(|exp| Some(exp))?;
+            let expiry = now.checked_add(exp).ok_or(Error::InvalidExpiry {
+                issued_at: now,
+                expiry: exp,
+            })?;
+
+            claims.exp = Some(expiry);
         }
 
         Ok(claims)