ARP not expiring

I'm having an issue with ARP not expiring -

User A (mac-address aa:aa:aa:aa:aa:aa) connects and gets a lease of 5 minutes per radius from Pool A (IP 172.17.46.35).
User then registers to gain access to network.
Client renews lease (due to 5min lease time) and gets new lease from Pool B per radius (IP X.X.X.X).

New user connects and gets assigned 172.17.46.35 (mac-address bb:bb:bb:bb:bb:bb).

This is what the arp and dhcp lease tables look like at this point -

[admin@router] > ip arp pri where mac-address =aa:aa:aa:aa:aa:aa
Flags: X - disabled, I - invalid, H - DHCP, D - dynamic, P - published

ADDRESS MAC-ADDRESS INTERFACE

0 D 172.17.46.35 aa:aa:aa:aa:aa:aa TENANT-ACCESS
1 D X.X.X.X aa:aa:aa:aa:aa:aa TENANT-ACCESS

[admin@router] > ip dhcp-server lease pri where active-address =172.17.46.35
Flags: X - disabled, R - radius, D - dynamic, B - blocked

ADDRESS MAC-ADDRESS

0 R PoolA bb:bb:bb:bb:bb:bb


The stale entry from the first users original lease persists in the table. It will not clear until manually removed. Time doesn't appear to make a difference, it will set there for hours if not manually cleared.

ROS 6.11

From ip settings -
arp-timeout: 30s

dhcp-server address pool is not set to static-only

I have this behavior happening on multiple routers.

Any direction is appreciated.

Thanks,

The latest supported version of routeros is 6.18

Yep, I will be upgrading in off hours, but I wanted to post in case someone had seen this before.

There is also ipsec policies for the networks on this router, just mentioning in case that is influencing arp behavior.

Thanks,