Auto update summary base on Single Issue Picker customfield

[Thảo Nguyễn]

Hi all,

I have a custom field with Type "Single Issue Picker" like this pic:

I hope I can auto update Summary field = Related RHR Ticket ( this custom field).

I try to use Automation Rule but It doesn't work like that:

Please help me if have any solutions for my problem!

Many thanks for all,