Error in plot + xlab(xlab) : non-numeric argument to binary operator

[imranjesar]

My Volcano plot is working fine for the argument on shape for all as below;
EnhancedVolcano(res_df,
lab = res_df$gene_sym,
x = 'log2FoldChange',
y = 'pvalue',
title = 'MSC Cellular RNA vs MSC Exosome',
pCutoff = 0.05,
FCcutoff = 1,
pointSize = 3.0,
labSize = 6.0,
colAlpha = 1)

But when i pass the argument for different shapes for my data it gives me the error;
Error in plot + xlab(xlab) : non-numeric argument to binary operator.
Code is as below
EnhancedVolcano(res_df,
lab = res_df$gene_sym,
x = 'log2FoldChange',
y = 'pvalue',
pCutoff = 0.05,
FCcutoff = 1,
cutoffLineType = 'twodash',
cutoffLineWidth = 0.8,
pointSize = 4.0,
labSize = 6.0,
shape = c(23,8,29),
colAlpha = 1,
legendLabels=c('Not sig.','Log (base 2) FC','p-value',
'p-value & Log (base 2) FC'),
legendPosition = 'right',
legendLabSize = 16,
legendIconSize = 5.0)