TypeError: Cannot read property “custbody_field” of null

To find the NetSuite script that is causing the error, follow these steps:

1. Go to Customization > Scripting > Scripted Records.
2. Edit the record that you’re trying to troubleshoot, say for example, “Sales Order”.
3. Look at the list of scripts deployed on the record defined by the “Deployed” checkbox.
4. Uncheck all the scripts under “User Event Scripts” or “Client Scripts”.
5. Go back to the form you are working on and try to replicate the error.
6. The error/issue will most likely stop after doing the previous step. To isolate the exact script that is causing the problem, tick the checkbox beside the script one by one. Take note of the last script that you enabled.
7. Try to replicate the error again by going to the form. If the error/issue starts to happen again, then it means you found the offending script.