pheatmap: incomplete figure

Dear R Community,
I tried to generate heatmap for a matrix of 1500 columns by 106 rows using the following R script:

pheatmap(tf.vs.DE.1.removeAllZeroCol, fontsize=3,border_color=NA)

and got the graph (as attached Fig 1)

Since the column labels appear very crowded, I tried to increase the cellwidth to stretch the graph horizontally. The idea was to show the graph section by section, but with clear/readable column labels (not overlapped labels).
So I typed:

pheatmap(tf.vs.DE.1.removeAllZeroCol, fontsize=3,cellwidth=3,cellheight=3,border_color=NA)

However, this time I only got middle part of the original heatmap (as attached Fig 2)
I wonder if there is way I could output the whole graph after such horizontal stretch. If not, how do I get the left end of the graph.
Thank you very much for any inputs!
Kind regards,
Ace
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