teamviewer requests always the same password

Hi,

 

i use Teamviewer since v10 with my mom's computer to connect on her computer when she has some troubles.

Since 1 year, and after several upgrades of teamviewer from 11 to 12, from 12 to 13 till v14, teamviewer always asks for the same pasword even if i set to reset password with 6 digits.

 

What's the problem ? How to force Teamviewer to request for a new password each time someone wants to connect on my mom's computer ?

thx