lodash set not working

[yasin459]

i have an object which i like to change one of the nested values
let the object be foldersData
then I run this code on lodash website:
let x= _.set({categories:foldersData} , "categories.folders[0].topicData.open" , 30023)

console.log("what",_.get(x , "categories.folders[0].topicData.open" , "nabbodd"))

which results in 30023
but when i run the EXACT code on vscode i GET TRUE(which is prevous value of given path)
which means that set is not working at all
strange thing is that I try the original example of https://lodash.com/docs/4.17.15#set and I am fine.
but with my own object it is not doing anything

[yasin459]

in case you needed folderData:
export var foldersData = { topicData: { title: "1موضوع", id: 1, parentId: 0, open: true, }, folders: [ { topicData: { title: "11موضوع", id: 10, parentId: 1, open: true, }, folders: [ { topicData: { title: "121موضوع", id: 10, parentId: 1, open: false, }, folders: [], files: [{ title: "کتگوری", open: false }], }, { topicData: { title: "12موضوع2", id: 10, parentId: 1, open: true, }, folders: [], files: [ { title: "کتگوری", open: true }, { title: "کتگوری", open: false }, { title: "کتگوری", open: false }, ], }, ], files: [{ title: "کتگوری" }, { title: "کتگوری" }], }, { topicData: { title: "12موضوع", id: 10, parentId: 1, open: false, }, folders: [], files: [ { title: "کتگوری", open: true }, { title: "کتگوری", open: false }, ], }, { topicData: { title: "13موضوع", id: 10, parentId: 1, open: true, }, folders: [], files: [ { title: "کتگوری", open: false }, { title: "کتگوری", open: false }, ], }, ], files: [], };