How to add new data when I have embedded existing_graph

[Benny1991-lucky]

I am using the Neo4jVector.from_existing_graph to create the node embedding.
existing_graph = Neo4jVector.from_existing_graph(
embedding=OpenAIEmbeddings(),
url=url,
username=username,
password=password,
index_name="person_index",
node_label="Person",
text_node_properties=["name", "location"],
embedding_node_property="embedding",
)

After that, I want to add new data to this Neo4jVector. How I can do? Delete the existing_graph and renew one?