Formatting a two variable plot animation - r

Question

I've seen other posts related to this error, but I'm really struggling to find the root cause of the error.
Basically, I'm trying to animate two lines A and B from values that are read through an Excel file. The plot is fine, but the error message appears when I try to animate it.
Here is the code:
library(tidyverse)
library(readxl)
library(here)
library(scales)
library(reshape)
library(stringr)
library(gganimate)
library(gifski)
real_format <- function(largest_with_cents = 100000) {
function(x) {
x <- round_any(x, 0.01)
if (max(x, na.rm = TRUE) < largest_with_cents &
!all(x == floor(x), na.rm = TRUE)) {
nsmall <- 2L
} else {
x <- round_any(x, 1)
nsmall <- 0L
}
str_c("R$", format(x, nsmall = nsmall, trim = TRUE, big.mark = ".", decimal.mark = ",", scientific = FALSE, digits=1L))
}
}
AB2000 <- read_excel(here("AxB_2000.xlsx"))
gg_base <- ggplot(data = AB2000) +
geom_line(aes(x = as.Date(Date), y = A, colour = "A", group = 1)) +
geom_line(aes(x = as.Date(Date), y = B, colour = "B", group = 1)) +
scale_color_manual(values = c("A" = "blue", "B" = "red"))
gg_base + labs(x = "Year",y = "") +
scale_y_continuous(expand = c(0,0),
breaks=seq(0,14000,1000),
labels=real_format()) +
theme_bw() + theme(panel.border = element_blank(),
panel.grid.major = element_blank(),
panel.grid.minor = element_blank(),
axis.line = element_line(colour = "black"),
legend.position="none")
gg_base.animation = gg_base + transition_reveal(Date)
animate(gg_base.animation, duration = 2, fps = 30, width = 800, height = 600)
anim_save("test.gif")
The excel table is the following:
I actually get an animation but it removes all the formatting. How can I keep the formatting from the plot?
I receive four message errors saying:
geom_line(): Each group consists of only one observation. ℹ Do you need to adjust the group aesthetic?
They don't appear if I don't animate (removing the three last lines of code).