Why is my manually created VCF file not opening on Android contacts app?

Sometimes it happens because the manual method does not generate VCF files properly, so that's why your files are not able to open in Android contact apps. So the solution is that you need to use a trustworthy software for accurate contact conversion. Now I'm using WholeClear CSV to VCF Converter for contact migration. This is an expert utility that effortlessly converts large CSV files into a clean VCF file. If you want to transfer all your contacts into VCF safely and accurately, you can use this CSV to VCF exporter. The tool works offline and smoothly runs on all Windows OS. After exporting the Contact in vCard format, you can easily import your contact into any Android device. You can first try this reliable tool with a free demo edition before purchasing