We had all these same problems before our September B2B on Explorer. Only way the reservations would stick was to ring Regent.

In the end it didn't really matter as we got any number of reservations at the specialty restaurants once on board at the dining times to suit us.

There is a dedicated office opposite reception where you can go at certain times during the day to make new/change dining reservations. It is a great improvement on the old system.

Sheila and Ken