Ansible regex to search and replace an IP Address in a line

I have an Ansible playbook where I need to change the Server Name in one line and an Specific IP address in another line, as in this line there are a bunch of IP address separated by a comma.

I have the below play which works absolutely fine in case I have to change the entire IP address line with the defined set of IP addresses, But I’m looking for specific IP address i.e. 191.168.1.4 to be looked upon and if found then just replace that only and leave the rest of the IP as it is.

Below is the Playbook…

In case below section not visible in above…

with_items:

I see the attachment is missing for the playbook section hence pasting it here again…