Import_vcf() error

I’m trying to import vcf file. However, a really critical problem has occurred. The problem is a specific field name contain backtick(`) at both ends, which has prevented me from analyzing my data.
This make me unable to select the field and replace the field name. In other word, I could not use that field.

How can I fix it? I posted the same question last time, but didn’t get any answers.
I really need to solve this problem. Please answer about my question.