Hi @Parth_Gupta
check your screenshot, list1 is actually meant to contain an array named "list" with the individual items, each of the form (and don't ask me why Adobe made it so complicated)
{
"value": "some value"
}
With your sample string (parts of it, I was too lazy to replicate the whole), a list1 data element could look somewhat like this
// customDimensions.lists.list1.list
let list1 = {
list: []
};
// you will likely use a _satellite.getVar to access the string value
const listData ="cif_2|accountNumber_108|sourceChannel_Branch|sourceChannel_API banking|sourcechannel_businessONLINE";
// break the string into an array of strings and create an object with a value key for each item
listData.split("|").forEach(item => list1.list.push({value: item}));
return list1;
Hope that helps
Cheers from Switzerland!