Julia Graphplot error "MethodError: no method matching get_adjacency_matrix(::SimpleDiGraph{Int64})"

I am using the following code in Julia v1.6 to plot a graph:

graphplot(network1, method=:chorddiagram, markersize=3, nodeshape=:rect, linecolor=:lightgrey)

where network1 is a {56, 445} directed simple Int64 graph

I am getting the following error:

MethodError: no method matching get_adjacency_matrix(::SimpleDiGraph{Int64})

I was able to find the method get_adjacency_matrix in the GraphRecipes package graphs.jl, and it looks like it might be expecting to be passed either an AbstractMatrix or and AbstractVector. The output I was expecting to get from this code looks like this: