Script to copy CRM company value to organisation

[Himanshu Nanda]

I'm using 'CRM for JIRA' for managing customer attributes. Using this I've created a CRM company field called "Customer" which is basically the customer name.
I've enabled the sync between Customer and Organisations in JIRA Service desk, so any new customer created in CRM automatically gets created in JSD.

Now, if a customer creates a ticket from the customer portal, the organisations is automatically set. But I need to set the same value for Customer as well.

Tried using the script mentioned here, but doesn't seem to work - https://community.atlassian.com/t5/Jira-Core-questions/Copy-Custom-field-value-from-one-field-to-another/qaq-p/73207

Please could you help me out on this? My ask is that when a ticket is created, as a listener or post function, the value of organisations should be copied to Customer field - when created from customer portal.

P.S. - I know organisations is a multi value field, but I'm using it only for a single value - i.e. the customer in questionl