i forgot my password how can i unlock my phone without erasing data?, and I don't have a backup.

Hello. If you forgot your password on your iPhone, there is no way to restore it without erasing all data on the device. Your best bet is to follow the instructions here and restore from a local or iTunes backup to get things up and running again.

So today you are learning the importance of a good back-up! Many of us have learned this lesson the hard way...

If you do not have a backup, your only option is to start over from scratch. As frazzm737 added, please ensure that you keep regular backups in the future using either your computer or iCloud.

Contact Apple and I still believe you can do by Forgot passowrd..

And I believe you are wrong. Erasing data when password is forgotten is a safety feature that prevents others from accessing your data.

Apple CSR is friend now...