Password

[xperia109]

after updating my phone to the new software my password to unlock my phone stopped working 

[Strampke]

Lost password means reset.

Sad but true.

[EMS_MO72]

If the lock screen password isn't working , you can try your Gmail password, if that didn't work too unfortunately that means a reset yes. You can do that by doing a software repair by the Xperia companion or you can reset it by Google find my device too.