If you are getting time out error while generating e-invoice from BUSY Accounitng Software you can check these things:
1:First,you need to check is there any portal issue or not.
2:Go to Administration menu,click configuration,click Features and options,then click GST/VAT,Check if the API is validating or not.
3:Here,validate both APIs and check which one is getting validated and which one is not.
4:If any API Webtel or Pinnacle is being validated as a GSP, then set that API in GSP for e-invoice,then go and generate again,
3:If Both API is not validating,so you need to check your internet should be properly working on your system.
4:If internet is properly working, you need to check if any antivirus on your system then exclude your BUSY and BUSYwin folder.
5:Check in window defender,BUSY should be allow from window defender firewall,
If its still showing that error it might be a PORTAL server issue in backend,so in that case you need to wait for some time when portal issue is resolve then you can generate e invoice, it will be genrated.