diff --git a/create_monthly_cash_flow.sh b/create_monthly_cash_flow.sh
index f42d124..a657a3e 100755
--- a/create_monthly_cash_flow.sh
+++ b/create_monthly_cash_flow.sh
@@ -333,6 +333,15 @@ done < <(find "$src_dir_cash_receipts" -maxdepth 1 -type f -name "rg-${year}-${m
 
 echo
 found_contract_file=false
+_month=$(expr $month + 1)
+_year=$year
+if [[ ${#_month} -eq 1 ]]; then
+   _month="0${_month}"
+elif [[ $_month -eq 13 ]]; then
+   _month=01
+   _year=$(expr $_year + 1)
+fi
+
 while IFS='' read -r -d '' file || [[ -n $file ]] ; do
    found_contract_file=true
    echononl "Copy '$(basename $file)' to directory\n '$dir_cash_flow'.."
@@ -343,7 +352,7 @@ while IFS='' read -r -d '' file || [[ -n $file ]] ; do
       echo_failed
       error $(cat $logfile)
    fi
-done < <(find "$base_dir_cash_flow" -mindepth 1 -maxdepth 1 -type f -name "ServiceVertraege_${year}_Stand-${year}-${month}-*.xlsx" -print0)
+done < <(find "$base_dir_cash_flow" -mindepth 1 -maxdepth 1 -type f -name "ServiceVertraege_${year}_Stand-${_year}-${_month}-*.xlsx" -print0)