Problem with ccr1036

Hello. we have two mikrotik ccr-1036-8G-2s +. Works as a PPPoE server.
It happens that it can not connect new users. Lost access to SNMP, ICMP, WINBOX. Users who were previously connected - are working properly. Helps only restart by wathdog or power reboot
sorry for my english

MAX CPU load 45%
max memory usage 700mb