bcftools merge works but outputs a merged vcf with some of the genotypes prefixed with "/" e.g. /0|0, /0|1, /1|1 etc

[mubita3]

I have successfully merged two VCF files using bcftools merge, but I note that the genotypes from the other(second) VCF file are preceded by "/" e.g. /0|0, /1|1,/0|1 etc.

The command I run is: (bcftools_env) mubita@dell:~/VCF-Simplify/createVCF$ bcftools merge global.vcf.gz chr6_7_17_geno_QC_ids.vcf.gz -O z -o combined.vcf.gz

When I input the output VCF in plink2, it returns an error "Error: Line 35 of --vcf file has an invalid GT field.¨. How can I get rid of the "/" before the genotypes in the merged VCF file?

I have sent the test files by email.

Kind regards, Mwangana