getting all daily oil prices from a dropdown menu in R

I am trying to get oil prices in all counties of Istanbul from this link:

https://www.petrolofisi.com.tr/akaryakit-fiyatlari

which has two dropdown list for selection of cities and counties, with the following code:

IST_DATA  <- data.frame(Sehir ="ISTANBUL",Ilce="ADALAR")
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="AVCILAR"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BAGCILAR"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BAHCELIEVLER"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BAKIRKOY"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BAYRAMPASA"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BESIKTAS"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BEYKOZ"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BEYOGLU"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="BUYUKCEKMECE"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="CATALCA"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="EMINONU"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="ESENLER"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="EYUP"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="FATIH"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="GAZIOSMANPASA"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="GUNGOREN"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="ISTANBUL_ANA"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="ISTANBUL_TRA"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="KADIKOY"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="KAGITHANE"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="KARTAL"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="KUCUKCEKMECE"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="MALTEPE"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="PENDIK"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="SARIYER"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="SILE"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="SILIVRI"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="SISLI"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="SULTANBEYLI"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="TUZLA"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="UMRANIYE"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="USKUDAR"))
IST_DATA  <- rbind.data.frame(IST_DATA,  data.frame(Sehir="ISTANBUL", Ilce="ZEYTINBURNU"))

FileData <- as.data.frame(NULL)

for(i in 1:nrow(IST_DATA))
{ 
 url <- sprintf("https://www.petrolofisi.com.tr/posvc/fiyat/guncel?il=%s&Ilce=%s", IST_DATA$Sehir[i], IST_DATA$Ilce[i])
 download.file(url,"petrolofisi.html", quiet=TRUE)
 AppendData <- as.data.frame(read_html("petrolofisi.html") %>% html_text(), stringsAsFactors=FALSE)     
 FileData <- rbind.data.frame(FileData,AppendData)
 rownames(FileData)[i] <- as.character(IST_DATA$Ilce[i])
}
View(FileData)
write_excel_csv2( x= FileData, path="AKARYAKIT.xls") 

and this resulted in a not-so-desired output like:

rownames did not show up in excel and data is not seperated into cells. How can I write this code more efficient so that:

1. I may not need to specify all counties in IST_DATA.
2. Get data exactly as a table as seen in web page.

Thank you very much for your help.