Q: unable to login the macbook pro in normal mode

Are you getting errors?

How are you logging in? Are you using Safe Mode?

What year/model MacBook Pro are you using, and what version os OS X are you running?

Have you tried to startup normally after starting in Safe Mode?

Try reseting NVRAM. How to Reset NVRAM on your Mac - Apple Support

If that does not help try some of the following:

Computer Won’t Start Up:

Try reseting SMC. Reset the System Management Controller (SMC) on your Mac - Apple Support

Then try a Safe Boot. Try Safe Mode if your Mac doesn't finish starting up

Also check out this help file. If your Mac won't turn on - Apple Support

Also check out this help file. Troubleshooting Startup and Login Items

Also check out this help file. Top 10 Troubleshooting Tips for Mac Startup Problems

Tackling Macs that always boot to Safe Mode. Tackling Macs that always boot to Safe Mode

Startup Screens :  About the screens you see when your Mac starts up

If none of these help:

Make a Genius Bar appointment:  Genius Bar

The evaluation will be FREE.

Kim