finally I found the problem was on the router2(IP:192.168.2.10) which is running a openwrt firmware.
After I remove this openwrt router out of the network spacedesk works fine.
maybe some openwrt feature is blocking some spacedesk traffic?
Network isolation is not activated on Router1.
I can ping my pc 192.168.2.229 on my cellphone correctly.
which port spacedesk use to transfer data? Is it related to firewall settings?