Same IP different MAC in ARP table & hotspot host

Hi,

Observed one issue in hotspot. MAC address in ARP table and Hotspot-Host is different but IP address is same. In this scenario, user cannot ping to hotspot and cannot get login page. After deleting both entries (ARP table and Hotspot-Host) new entry comes and everything is normal. Fail to understand what is causing this issue.

The setup is as below:

Hotspot
Server - idle timeout - 10 mins
User profile - Session timeout - 10 hrs, Idle timeout - 50 mins

DHCP server
Lease time- 4 hrs
Add ARP for leases - yes

Thanks.