Hotspot Hijack MAC address

hello, i’ve setup a hotspot in my network the problem is that the hotspot is responding to ARP packets of other hosts, example in my arp table i see 10.19.91.254 max xx.xx.xx.xx.xx.11 it correct but i see too 10.19.91.35 xx.xx.xx.xx.xx.11, i hope you understand my bad english, i’m usin arp=enabled and try with proxy-arp too. but the sae problem.

Try with this:
IP → Hotspot → Server → your hotspot → Address Pool = None

Anyway I thought it only happend in 2.x versions of routeros. What version is it?