Debezium Error : ConnectException: Data row is smaller than a column index

library(dplyr);
df %>% group_by(item) %>% mutate(smaller = c(diff(val) < 0, F), 
                                 next.smaller.day = ifelse(smaller, lead(day), -1)) %>%
       select(-smaller)

# Source: local data frame [6 x 4]
# Groups: item [2]

#    item   day   val next.smaller.day
#   <int> <int> <int>            <dbl>
# 1     1     2     3                4
# 2     1     4     2                5
# 3     1     5     1               -1
# 4     2     1     1               -1
# 5     2     3     2               -1
# 6     2     5     3               -1

find.next.smaller <- function(ini = 1, vec) {
    if(length(vec) == 1) NA 
    else c(ini + min(which(vec[1] > vec[-1])), 
          find.next.smaller(ini + 1, vec[-1]))
}       # the recursive function will go element by element through the vector and find out 
        # the index of the next smaller value.

df %>% group_by(item) %>% mutate(next.smaller.day = day[find.next.smaller(1, val)], 
                                 next.smaller.day = replace(next.smaller.day, is.na(next.smaller.day), -1)) 

# Source: local data frame [6 x 4]
# Groups: item [2]
#
#    item   day   val next.smaller.day
#   <int> <int> <dbl>            <dbl>
# 1     1     2     2                5
# 2     1     4     3                5
# 3     1     5     1               -1
# 4     2     1     1               -1
# 5     2     3     2               -1
# 6     2     5     3               -1

def get_val(location, weight, df):
    col = df.columns[0]
    for c in df.columns:
        if weight >= int(c):
            col = c
        else:
            break
    return df.loc[location, col]
get_val(1, 500, data_frame_test)