Analyzing PBMC scATAC-seq Using Signac Error

Question

[Sohum]

Hi. I am trying to follow the directions at https://stuartlab.org/signac/articles/pbmc_vignette to analyze ATAC-seq data. However, I am running into the error "Error: unable to find an inherited method for function 'mcols' for signature 'x = "NULL"'" and am not sure what the issue is. I am new to bioinformatics and R. Any guidance would be appreciated.

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