Hi Satish,
Thank you for reaching out. It is still not currently possible to add/remove members of a UserList using Google Ads API. It is only possible in AdWords API using the
mutateMembers call. If you are able to use AdWords API, I suggest using it for this feature. A feature request for this has been put in place for this in the Google Ads API, so please keep an eye out on our
blog for any updates.
Regards,
Danica, Google Ads API Team

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