Errors occurred when running gosh.diagnostics() function in dmetar package

Question

I've been working on a meta-analysis project which involved the sophisticated GOSH plot to explore the between-study heterogeneity (Olkin et al., 2012). To further identify the potential outliers, I adopted the method proposed by Harrer et al. as described in a comprehensive guide (https://bookdown.org/MathiasHarrer/Doing_Meta_Analysis_in_R/gosh-plot-analysis.html). In specific, the gosh.diagnostics() function uses three unsupervised machine learning algorithms to detect clusters in the GOSH plot data and determine which studies contribute the most to them automatically. As I run this function, most of the time it gave me results without errors. However, this time it came back with an error saying "Error in [.data.frame(dat.db.full, db.plot.mask, c(3, 6, outlier.studies.all.mask)) : undefined columns selected". Could someone please tell me what the problem might originate from and the possible solution to it?

Here's my code.

# install required packages
install.packages("devtools")
devtools::install_github("MathiasHarrer/dmetar")
install.packages("metafor")

# load required packages
library(metafor)
library(dmetar)

# Create data set

TE <- c(0.693147181,
        0.932164081,
        0.759870813,
        0.937269138,
        1.688249093,
        0.955511445,
        0.91228271,
        0.353,
        1.638258578,
        2.592980871,
        0.587786665,
        1.098612289,
        0.815364813,
        0.444685821,
        0.841567186,
        -0.589606502
)

seTE <- c(0.332562268,
          0.403827718,
          0.280396018,
          0.432861017,
          0.196494688,
          0.453186734,
          0.47468172,
          0.174,
          0.379343294,
          1.444715875,
          0.276176517,
          0.383693213,
          0.417546777,
          0.218181816,
          0.663200487,
          1.081238182
)

author <- seq(16)

df <- data.frame(author, TE, seTE)

# Fit the data
m.rma.df <- rma(yi = df$TE, 
                sei = df$seTE,
                method = "DL")

# plot GOSH plot
dat.gosh.df <- gosh(m.rma.df)

# Run diagnostics
gosh.diagnostics(dat.gosh.df)