R error with gap.plot: origin must be supplied - r

Question

I am using the gap.plot function to make a graph that spans across a multi-year data-set. However, with the first series I am trying to add it's already giving me issues with respect to the origin:
Error in as.Date.numeric(e) : 'origin' must be supplied
I looked at the typical things to try to resolve this, and I think I am using the correct function to transform the timestamps. The dataset looks fine.
My code is as follows:
setwd("~/PhD/4 Field experiment/Harvest data")
##### data weergeven #####
BioAvg<-read.csv("Alex Copy of Biomass (average).csv", header=T, na="", stringsAsFactors=TRUE)
class(BioAvg$Time)
class(BioAvg$Harvest)
class(BioAvg$Time)<-"Date"
BioAvg$Time2<- as.Date(BioAvg$Time, origin="1970-01-01")
BioAvg2<-BioAvg[1:15,]
plot.new()
par(bty="n")
gap.plot(BioAvg2$Time, BioAvg2$X0EW.0P, gap=c(17850,18000, 18230,18300), gap.axis = "x",pch = 19, col = "gray55",
type="o", lwd=2, ylab = "Aboveground biomass (g)", xlab= "Time",
xtics = c(17600:17850,18000:18230,18300:18430), xticlab = c(May:Nov,Jun:Nov,Apr:Jun))
P.s. there are more graphs to be added later on in the code, otherwise gap.plot would not make sense indeed. But this is the minimum code needed to reproduce the error.
The CSV file with data:
https://drive.google.com/file/d/1IdfiSnEeSHWu4s52l0RCgqTahNe-3cNL/view
Many thanks for the advice