cant load due to an error about listening

[jamieduk]

root@jnet:/var/www/html/apps/games/Connect4/MP# sudo ./Run.sh
/var/www/html/apps/games/Connect4/MP/server.js:7
io = require('socket.io').listen(server);
^

TypeError: require(...).listen is not a function
at Object. (/var/www/html/apps/games/Connect4/MP/server.js:7:28)
at Module._compile (node:internal/modules/cjs/loader:1101:14)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1153:10)
at Module.load (node:internal/modules/cjs/loader:981:32)
at Function.Module._load (node:internal/modules/cjs/loader:822:12)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
at node:internal/main/run_main_module:17:47

any ideas?

Im trying to use 3001 as already using 3000 I changed it in file and it wont start.