I am transferring a project over to a new server (VPS). I am getting some weird JS issues. Script links are fine and I can load them via the inspection console and read the file, BUT they are throwing some Uncaught Type Errors.

This worked fine on the old server. I am assuming it is a config issue the project uses Symfony as a framework. I have updated the URL within the routing process but still nothing.

custom.js:18 Uncaught TypeError: jQuery(...).singlePageNav is not a function
    at HTMLDocument.<anonymous> (custom.js:18:17)
    at j (jquery-1.11.1.min.js:2:27244)
    at Object.fireWith [as resolveWith] (jquery-1.11.1.min.js:2:28057)
    at Function.ready (jquery-1.11.1.min.js:2:29891)
    at HTMLDocument.J (jquery-1.11.1.min.js:2:30257)
(anonymous) @ custom.js:18
j @ jquery-1.11.1.min.js:2
fireWith @ jquery-1.11.1.min.js:2
ready @ jquery-1.11.1.min.js:2
J @ jquery-1.11.1.min.js:2


Uncaught TypeError: Cannot read properties of null (reading 'addEventListener')
    at functions-min.js:1:996
    at Array.forEach (<anonymous>)
    at o (functions-min.js:1:185)
    at d (functions-min.js:1:975)
    at k.init (functions-min.js:1:9034)
    at k.I (functions-min.js:1:2023)
    at new k (functions-min.js:1:4627)
    at w (functions-min.js:1:2080)
    at new ct (functions-min.js:1:7533)
    at new lt (functions-min.js:1:7314)