[Reg] Error in plot generating

[anjY123]

plot_attack_rates( inf_chain, titre_dat, strain_isolation_times, n_alive = NULL, pointsize = 1,
fatten = 0,pad_chain = TRUE,prior_pars = NULL, plot_den = FALSE, true_ar = NULL,
by_group = FALSE, group_subset = NULL, plot_residuals = FALSE, colour_by_taken = TRUE,
by_val = 5)
Error in if (is.na(x)) { : the condition has length > 1

When i try to run this plot am getting this error, how can i fix this error, pleases help me.

Thank You