Password problem in Android Secure Online Backup client

I cannot use the app because it does not handle passwords properly.

I use very strong passwords (15 characters, mixed case, numbers, and symbols - and they always start with a letter for compatibility) and manage them with LastPass.

I cannot log into Secure Online Backup from Android because the app does not conform to best practices for password handling. I tried to enter my password from LastPass and also manually with no success. I have no issues with logging into the web client for Secure Online Backup so it is very likely that the problem lies within the Android client's authentication function.

Curiously, the Cox Mobile Connect apps works fine (same username and password) and I have no problem logging into it (or dozens of other online accounts with similarly strong passwords).

Please notify whomever is responsible for application development.

edit: I changed my Cox password in an attempt to resolve the problem or at least narrow it down. The new password did not contain any characters or combinations likely to cause a problem. My guess is that the length of the password is the problem. Handling 15 character passwords should be a no-brainer. Every other Android app I use does it.