802.1X认证，radius服务器状态总是翻转。

客户现场一台S5570交换机，配置了802.1X认证，在桌管后台看到用户正常认证，并且看到认证节点为本台交换机，在交换机上看到用户认证正常，但是radius状态总是为blocked状态，看交换机日志，一直在active和blocked之间翻转。交换机到radius服务器之间通信正常，1812和1813端口都是开通的，没有策略阻拦。请问是什么问题？交换机版本的问题吗？

日志如下：

%Sep 19 13:54:02:693 2025 12F-OA-S5570-01 RADIUS/6/RADIUS_ACCT_SERVER_UP: RADIUS accounting server became active: server IP=10.3.1.1, port=1813, VPN instance=public.

%Sep 19 13:54:08:867 2025 12F-OA-S5570-01 RADIUS/4/RADIUS_AUTH_SERVER_DOWN: RADIUS authentication server was blocked: server IP=10.3.1.1, port=1812, VPN instance=public.

%Sep 19 13:54:17:865 2025 12F-OA-S5570-01 RADIUS/4/RADIUS_AUTH_SERVER_DOWN: RADIUS authentication server was blocked: server IP=10.3.1.2, port=1812, VPN instance=public.

%Sep 19 13:54:31:864 2025 12F-OA-S5570-01 RADIUS/4/RADIUS_ACCT_SERVER_DOWN: RADIUS accounting server was blocked: server IP=10.3.1.1, port=1813, VPN instance=public.

%Sep 19 13:54:33:693 2025 12F-OA-S5570-01 RADIUS/6/RADIUS_ACCT_SERVER_UP: RADIUS accounting server became active: server IP=10.3.1.1, port=1813, VPN instance=public.

%Sep 19 13:54:50:862 2025 12F-OA-S5570-01 RADIUS/4/RADIUS_ACCT_SERVER_DOWN: RADIUS accounting server was blocked: server IP=10.3.1.1, port=1813, VPN instance=public.

%Sep 19 13:54:52:696 2025 12F-OA-S5570-01 RADIUS/6/RADIUS_ACCT_SERVER_UP: RADIUS accounting server became active: server IP=10.3.1.1, port=1813, VPN instance=public.

%Sep 19 13:55:43:879 2025 12F-OA-S5570-01 RADIUS/6/RADIUS_ACCT_SERVER_UP: RADIUS accounting server became active: server IP=10.3.1.2, port=1813, VPN instance=public.