Use this if you are using igraph from R
Delete a vertex attribute
delete_vertex_attr(graph, name)
| graph | The graph | 
| name | The name of the vertex attribute to delete. | 
The graph, with the specified vertex attribute removed.
Other graph attributes: delete_edge_attr,
delete_graph_attr,
edge_attr<-, edge_attr_names,
edge_attr, graph_attr<-,
graph_attr_names, graph_attr,
igraph-dollar,
igraph-vs-attributes,
set_edge_attr,
set_graph_attr,
set_vertex_attr,
vertex_attr<-,
vertex_attr_names,
vertex_attr
g <- make_ring(10) %>%
  set_vertex_attr("name", value = LETTERS[1:10])
vertex_attr_names(g)
g2 <- delete_vertex_attr(g, "name")
vertex_attr_names(g2)