Is there a way to suppress a specific message from syslog?

[pseu_asus]

Hi, guys,
My AX-56U router recently got overwhemled by a specific msg in syslog, it looked like this format:

Mar 14 13:21:26 kernel: TCP: mptcp_fallback_infinite 0x******** will fallback - pi 1, src [source IP address: my router LAN IP ] dst [destination IP address, Internet IP addr.] from tcp_rcv_state_process+0x***/0x***

I got thousands of them, making me hard to find other critical information. I have increased my syslog size to 2048 by

nvram set log_size=2048

admin@RT-AX56U:/tmp#

grep "kernel: TCP: mptcp_fallback_infinite" /tmp/syslog.log | wc -l

3749
admin@RT-AX56U:/tmp#

grep "kernel: TCP: mptcp_fallback_infinite" /tmp/syslog.log-1 | wc -l

6646

Is there a way to suppress this specific message from syslog? If so, I want to exclude "Kernel.TCP.mptcp" info out. [Looks like this is multi-TCP fallback, because I turned on dual WAN with Load Balance mode.]

I did not find the syslogd conf file at /etc/syslog.conf or somewhere else. Is there a way to achieve this in ASUS router?