CASE : ARP table overflow, please consider increasing max-arp-entries
resolve : /ip settings set max-arp-entries=16384
(16384 = 16Mx1024)
I opened a ticket on "changeip.com" and they told me the following
We have identified a problem that is affecting use of updates via devices and scripts. A fix is being implemented and should be in place within the next 24 hours. Thank you for your patience.