diff --git a/src/PaymentServer/Main.hs b/src/PaymentServer/Main.hs
index e337919c1e0e93326e234de0aa2b439039534ee0..41a44501fd873731489948e2c6079c1908088d0a 100644
--- a/src/PaymentServer/Main.hs
+++ b/src/PaymentServer/Main.hs
@@ -11,6 +11,7 @@ import Text.Printf
   )
 import Data.Maybe
   ( maybeToList
+  )
 import Data.ByteString
   ( ByteString
   )