jquery.js:9664 GET https://{{ domain }}/admin/index.php?route=extension/theme/BurnEngine&controller=layoutBuilder&action=index&store_id=0&token={{generated_token}} 503

Request URL: https://{{ domain }}/admin/index.php?route=extension/theme/BurnEngine&controller=layoutBuilder&action=index&store_id=0&token={{generated_token}}
Request Method: GET
Status Code: 503
Remote Address: 85.0.0.0:443
Referrer Policy: no-referrer-when-downgrade

alt-svc: quic=”:443″; ma=2592000; v=”35,39,43″
cache-control: private, no-cache, no-store, must-revalidate, max-age=0
content-length: 629
content-type: text/html
date: Sun, 09 Dec 2018 09:53:43 GMT
pragma: no-cache
server: LiteSpeed
status: 503

route: extension/theme/BurnEngine
controller: layoutBuilder
action: index
store_id: 0
token: {{generated_token}}

The thing is that it workes on my local server, I kinda thinking this is might be a server related issue.

// Do send the request
// This may raise an exception which is actually
// handled in jQuery.ajax (so no try/catch here)
xhr.send( ( options.hasContent && options.data ) || null );