Error on converting dat data to dataframe : arguments imply differing number of rows: 1074, 12

I'm trying to convert dat data to data frame using the code however it is giving the mentioned error. Any help will be highly appreciated. the data file is also attached https://drive.google.com/file/d/1y7IMpsnrCXSZXXFU4F6SUvDUFGeWPAnt/view?usp=sharing

Code So Far:

library(XML)
require(plyr)
library(stringr)
dat <- readLines("NTISDATD-Events-2020-05-10-Day8.dat")

datDF <- data.frame(
    tags = unlist(str_extract_all(dat, "<([^>]*)>(?=[^>]*</\\1>)")),
    values = unlist(str_extract_all(dat, "(?<=<([^>]{1,100})>).*(?=</\\1>)"))
) 
datDF

Desired Output:

                       tags                        values
 1            <d2lm:country>                            gb
 2 <d2lm:nationalIdentifier>                          NTIS
 3           <d2lm:feedType>                    Event Data
 4    <d2lm:publicationTime> 2020-05-10T00:00:44.778+01:00
 5            <d2lm:country>                            gb
 6 <d2lm:nationalIdentifier>                          NTIS
 7     <d2lm:areaOfInterest>                      national

Many Thanks