How to delete a nested object inside array of objects

I am trying to delete an object property. I used splice method, also delete method, but I receive “TypeError: Cannot delete property.”. I have a comments array, whose each comment object has replies array of objects, and I am trying to delete one of the object (reply object whose id is 1) inside replies array. And then replacing this comment object with its old version inside commments array. I tried:

comments[localId].replies.splice(1, 1)  // cannot delete property
comments[localId].replies = comments[localId].replies.filter((reply) => reply.id !== 1)  // nothing changing unexpectedly

How can I handle this issue?