HA usually happens twice a day and i found this log:
HA proc_running bd fails action is go offline and down links. HA daemon_heartbeat bd fails action is restart. HA proc_running bd is now responding.
I also checked document k20125635 but did not see that bug.
F5 firmware version is 220.127.116.11
What other things should I check or what is the solution to fix this problem?
You can start checking whether ASM process restarted before this HA incedent or not, because this might be one of the reasons, also, disk space issues. check available space on devices.
your f5 device its alright of resources? for the log and documentations of similars case, them goes indicated problem on resources(ASM module consume a lot of them)