Inside, you may find file(s) like CONTACT_JSON.zip , Contact.bk , or SmartSwitchBackup.json . If you're lucky, you'll find a standard .json file containing your contact information. You could then parse this JSON data and convert it to VCF format using a script or an online JSON-to-VCF converter. This is a technical process with no guarantee of success and is best left to experienced users.
Install a trusted SPBM to VCF converter. spbm file to vcf link
Several free online converters allow you to convert without downloading software. Inside, you may find file(s) like CONTACT_JSON