Error with link_dam_metadata(metadata, result_dir = DATA_DIR)

[christinachan520]

Hi, I'm trying to use it for the first time and am getting this error:
Error in vecseq(f__, len__, if (allow.cartesian || notjoin || !anyDuplicated(f__, :
Join results in 3072 rows; more than 192 = nrow(x)+nrow(i). Check for duplicate key values in i each of which join to the same group in x over and over again. If that's ok, try by=.EACHI to run j for each group to avoid the large allocation. If you are sure you wish to proceed, rerun with allow.cartesian=TRUE. Otherwise, please search for this error message in the FAQ, Wiki, Stack Overflow and data.table issue tracker for advice.

Here is my code:
getwd()
DATA_DIR <- getwd()
list.files(DATA_DIR)
setwd(DATA_DIR)
metadata <- fread("Metadata_Experiment1C.csv")
metadata
DATA_DIR
metadata <- link_dam_metadata(metadata, result_dir = DATA_DIR)

My DAM data and Metadata files are attached to this document
Monitor22_Experiment1.txt
Monitor23_Experiment1.txt
Monitor21_Experiment1.txt
Metadata_Experiment1C.csv

Thank you!