how to gain the sequence information

[zhoudreames]

I get the vcf files with graphtyper, but the column of REF and ALT doesn't contain sequence information. For example: but I want to gain such format, the REF and ALT shown as G and GAAAAGTAAACTTGGGAGTTCCCAT...., how to gain such format ？ thanks~

#CHROM  POS     ID      REF     ALT     QUAL    FILTER  INFO    FORMAT
chr2    8005860 chr2:8005860:DG G GAAAAGTAAACTTGGGAGTTCCCATT.....