What is the reason for periodic DNS doctoring dumps on Cisco ASA?

Question

Domain Name System

Greetings. There is a network object in the DMZ zone (Static NAT). DNS doctoring is enabled so that the local address from the local area is resolved by the name site.ru
Periodically, it happens that the ASA does not rewrite dns and the external address is resolved inside. It goes away on its own after about 40 minutes.
I can also note the moment that there is a similar object in the DMZ zone with the same settings, but there are no problems with it.
Thank you.