diff --git a/library/src/calculate_price.cpp b/library/src/calculate_price.cpp
index 0041d08..cdb5a98 100644
--- a/library/src/calculate_price.cpp
+++ b/library/src/calculate_price.cpp
@@ -946,6 +946,8 @@ CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(
 
 
             QDateTime effectiveStartTime(start_parking_time);
+            qCritical() << __func__ << ":" << __LINE__ << "effectiveStartTime:"
+                        << effectiveStartTime.toString(Qt::ISODate);
 
             // handle special days
             int const specialDayId = tariff->specialDayId(start_parking_time);
@@ -976,6 +978,9 @@ CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(
                 }
             }
 
+            qCritical() << __func__ << ":" << __LINE__ << "effectiveStartTime:"
+                        << effectiveStartTime.toString(Qt::ISODate);
+
             // handle prepaid option
             int const prepaid_option_id = tariff->getPaymentOptions(paymentOptionIndex).pop_prepaid_option_id;
             std::optional<ATBPrepaid> prepaidOption = tariff->getPrepaidType(prepaid_option_id);
@@ -990,17 +995,36 @@ CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(
 
                     if (start_parking_time.time() < p.prepaid[weekDay].static_end) {     // static_end: e.g. 08:00:00
                         effectiveStartTime.setTime(p.prepaid[weekDay].static_end);
+                        qCritical() << __func__ << ":" << __LINE__ << "effectiveStartTime:"
+                                    << effectiveStartTime.toString(Qt::ISODate);
                     } else
                     if (start_parking_time.time() > p.prepaid[weekDay].static_start) {   // static_start: e.g. 22:00:00
-                        effectiveStartTime.setTime(p.prepaid[weekDay].static_start);
+                        QTime const midnight(23, 59, 59);
+                        QTime const midnight24(0, 0, 0);
+
+                        if ((p.prepaid[weekDay].static_start <= midnight && midnight24 <= p.prepaid[weekDay].static_end)
+                         || (p.prepaid[weekDay].static_start == midnight && midnight == p.prepaid[weekDay].static_end)
+                         || (p.prepaid[weekDay].static_start == midnight24 && midnight24 == p.prepaid[weekDay].static_end)) {
+                            effectiveStartTime = effectiveStartTime.addDays(1);
+                            weekDay = effectiveStartTime.date().dayOfWeek();
+                            qCritical() << __func__ << ":" << __LINE__
+                                        << "effectiveStartTime: new week day [" << weekDay << "] (Mon=1, Tue=2, ..., Sun=7)";
+                        }
+                        effectiveStartTime.setTime(p.prepaid[weekDay].static_end);
+                        qCritical() << __func__ << ":" << __LINE__ << "effectiveStartTime:"
+                                    << effectiveStartTime.toString(Qt::ISODate);
                     }
                 }
+            } else {
+                qCritical() << __func__ << ":" << __LINE__ << "no prepaid option set";
             }
 
+            // set seconds to 0
             effectiveStartTime.setTime(QTime(effectiveStartTime.time().hour(),
                                              effectiveStartTime.time().minute(), 0));
 
-            qCritical() << __func__ << ":" << __LINE__ << "effectiveStartTime:" << effectiveStartTime.toString(Qt::ISODate);
+            qCritical() << __func__ << ":" << __LINE__ << "effectiveStartTime:"
+                        << effectiveStartTime.toString(Qt::ISODate);
 
             int const carryOver = tariff->getPaymentOptions(paymentOptionIndex).pop_carry_over;
 
@@ -1023,12 +1047,12 @@ CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(
                     s = s.addSecs(minutesUntilCarryOver * 60);
                     s = s.addSecs(carryOverDuration * 60);
                     end_parking_time = s.addSecs(rest * 60);
+                    qCritical() << __func__ << ":" << __LINE__ << "end-parking-time:" << end_parking_time.toString(Qt::ISODate);
                 } else {
                     end_parking_time = effectiveStartTime.addSecs(netto_parking_time*60);
+                    qCritical() << __func__ << ":" << __LINE__ << "end-parking-time:" << end_parking_time.toString(Qt::ISODate);
                 }
 
-                qCritical() << __func__ << ":" << __LINE__ << "end-parking-time:" << end_parking_time.toString(Qt::ISODate);
-
                 weekDay = end_parking_time.date().dayOfWeek();
 
                 // musste man in einer schleife machen