nordic52840 ancsc reconnection causes system reset

Hello, I have a question.

1. When ancs is reconnected, the machine will be reset, and the software will catch the log as follows.

As long as there are a large number of unread messages on the mobile phone (IOS system), such as qq, SMS, phone, WeChat, etc., ancs will report an error as long as it is reconnected, resulting in the reset of the machine. When there are fewer unread messages on the mobile phone, there will be no problem.

Please help to look at this problem, thank you!

The SDK version: nRF5_SDK_15. 0.0 _a53641a \ examples \ ble_peripheral \ ble_app_ancs_c \ pca10056 \ s140 \ arm5_no_packs

Protocol line: s140_softdevice-hex

Platform: nordic52840.