RTL8125B 2.5GbE does not switch to media 2500Base-T mediaopt full-duplex

[fundon]

I installed the realtek-re-kmod, and enable the kernel module.

Setings:
ifconfig_re0="inet 192.168.0.30 netmask 255.255.255.0 media 2500Base-T mediaopt full-duplex"
ifconfig_re0_ipv6="inet6 accept_rtadv"

re0:
media: Ethernet Other <full-duplex> (1000baseT <full-duplex>)
status: active

bsdconfig networking
selected the media 2500Base-T mediaopt full-duplex

but use iperf3 test it just have 1000Mb

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Server listening on 5201 (test #1)
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Accepted connection from 192.168.0.13, port 51751
[ 5] local 192.168.0.30 port 5201 connected to 192.168.0.13 port 51752
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 110 MBytes 922 Mbits/sec 47 91.2 KBytes
[ 5] 1.00-2.00 sec 109 MBytes 917 Mbits/sec 48 57.0 KBytes
[ 5] 2.00-3.00 sec 109 MBytes 918 Mbits/sec 47 137 KBytes
[ 5] 3.00-4.00 sec 110 MBytes 919 Mbits/sec 47 174 KBytes
[ 5] 4.00-5.00 sec 110 MBytes 919 Mbits/sec 47 225 KBytes
[ 5] 5.00-6.00 sec 109 MBytes 917 Mbits/sec 48 254 KBytes
[ 5] 6.00-7.00 sec 110 MBytes 919 Mbits/sec 47 265 KBytes
[ 5] 7.00-8.00 sec 110 MBytes 919 Mbits/sec 48 12.8 KBytes
[ 5] 8.00-9.00 sec 109 MBytes 918 Mbits/sec 48 22.8 KBytes
[ 5] 9.00-10.00 sec 110 MBytes 919 Mbits/sec 47 42.8 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 1.07 GBytes 919 Mbits/sec 474 sender
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Server listening on 5201 (test #2)
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