The Reasons For AP Disconnecting

There exists a question discussed hotly, How does AP disconnect and then get in touch? Everybody can show your ideas right here. The AP of the 2504WLC 1602 can be registered usually, but when I check the record, AP is disconnected after which reconnected.
The main logs tend to be as follows:

37
Mon Mar 25 09:28:06 2019
AP’s Interface:1(802.11a) Operation State Up: Base Radio MAC:00:6c:bc:c3:f8:80 Cause=Unknown Reset Status:NA
38
Mon Mar 25 09:28:06 2019
AP’s Interface:0(802.11b) Operation State Up: Base Radio MAC:00:6c:bc:c3:f8:80 Cause=Unknown Reset Status:NA
39
Mon Mar 25 09:28:06 2019
AP’s Interface:0(802.11b) Operation State Up: Base Radio MAC:00:6c:bc:c3:fa:70 Cause=Unknown Reset Status:NA
40
Mon Mar 25 09:28:05 2019
AP’s Interface:1(802.11a) Operation State Down: Base Radio MAC:00:6c:bc:c3:fa:70 Cause=Radio interface reset. Status:NA
41
Mon Mar 25 09:28:05 2019
AP ‘APe00e.daa6.508f’, MAC: 00:6c:bc:c3:f8:80 disassociated previously due to Link Failure. Uptime: 4 days, 22 h 36 m 31 s . Reason: Capwap WTP Event request.
42
Mon Mar 25 09:28:05 2019
AP ‘APe00e.daa6.50ae’, MAC: 00:6c:bc:c3:fa:70 disassociated previously due to Link Failure. Uptime: 4 days, 23 h 47 m 32 s . Reason: Capwap WTP Event request.

The reason why maybe are:
1. A problem with its hardware.
2. A problem with the wireless channel. The actual channels are not separated.
3. The influence of wifi.
4. The insufficient bandwidth is not enough.