showing error tkn error

If you want to enter a quotation character, then you need to add two quotation characters in a string e.g.

Keys("VTN:'S2F23' W\r\n<L[[5]\r\n <U4[[1] 1>/* TRID */\r\n <A[[6] ""00000050"">/* DSPER 6 ASCII in hhmmss or 8 ASCII hhmmsscc */");

or use \"

Keys("VTN:'S2F23' W\r\n<L[[5]\r\n <U4[[1] 1>/* TRID */\r\n <A[[6] \"00000050\">/* DSPER 6 ASCII in hhmmss or 8 ASCII hhmmsscc */");