Am failing to transfer some contacts from my old iphone6 to iphone x

Hello stone32,

Thanks for posting in Apple Support Communities. Contacts on your iPhone are connected to an email account, whether that is iCloud or a third-party account. Since you are missing some contacts, make sure that all accounts appear and have Contacts selected using these steps from Manage and delete contacts on your iPhone or iPad - Apple Support.

"Turn Contacts on or off for an account

Want to add or remove all of the contacts from an account that you already set up? Just turn Contacts on or off for that account:

1. Go to Settings > Contacts > Accounts.
2. Tap the account that has contacts that you want to add or remove.
3. To add contacts, turn on Contacts. To remove contacts, turn off Contacts, then tap Delete from My iPhone."

If you are missing any email accounts, you can also add them using the guidance in Add an email account to your iPhone, iPad, or iPod touch - Apple Support.

"How to set up your email account automatically

If you use an email provider like iCloud, Google, or Yahoo, Mail can automatically set up your email account with just your email address and password. Here's how:

1. Go to Settings > Mail, then tap Accounts.
2. Tap Add Account, then select your email provider.
3. Enter your email address and password.
4. If you see Next, tap Next and wait for Mail to verify your account.
5. If you see Save, tap Save."

Take care.