diff --git a/R/CreateInputsModel.R b/R/CreateInputsModel.R
index c133ed7d3ad82e1ba88eb32da266e7bfa8ae2ea1..9ee5d4c6671c85b9b5c5934da3ef7e8c967b0871 100644
--- a/R/CreateInputsModel.R
+++ b/R/CreateInputsModel.R
@@ -216,9 +216,7 @@ CreateInputsModel <- function(FUN_MOD,
     if(any(LengthHydro > 1000)) {
       warning("The unit of 'LengthHydro' has changed from m to km in v1.7 of airGR: values superior to 1000 km seem unrealistic")
     }
-    if (!(QupstrUnit %in% c("mm", "m3", "m3/s", "l/s", "L/s"))) {
-      stop("'QupstrUnit' must be one of these values: 'mm', 'm3', 'm3/s', 'L/s' or 'l/s'")
-    }
+    QupstrUnit <- match.arg(arg = QupstrUnit, choices = c("mm", "m3", "m3/s", "l/s", "L/s"))
   }
 
   ##check_NA_values