Targeting 2 list on the same call

Hi everyone,

I would love to obtain some help if possible this may be a very basic question but is cracking my head and the options I found don’t seem to work:

In the body of my request I have the following;

{
“name”: “TEST1”,
“campaign_id”: “SP1”,
“options”: {
“start_time”: “2022-05-05T20:35:00”
},
“recipients”: {
“list_id”: “test”,
“list_id”: “test1”,
},
“content”: {
“template_id”: “SP1”
}
}

What I’m trying to accomplish is to schedule an email to List X and List Y at a specific time on the same query.

Details (like screenshots):