This looks like it refers to the same data as Brant posted here.
Brant: In the code block you posted, the second half of the code overrides the first half — could remove the first half, meaning the half ends at "Step 1"?
Also, a reprex would help, and for this topic, aggregate data would be good. Could run the following code and post the output?
library(tidyverse)
data <- read.csv("fifteenminuteintervaldata.csv")
data |>
separate_wider_delim(
cols = Date,
names = c("year", "month", "day"),
delim = '-',
cols_remove = F) |>
group_by(year, month) |>
summarise(
Precipitation = sum(Precipitation),
Discharge = sum(Discharge)
) |>
dput()