Cancel Subscription function not possible for LONG passwords with special characters

[cheaty]

I experienced that the cancel subscription function doesn't work if your account uses really long, really complex passwords.

(such as: V^EJW%|n7Bs?~!ip]vnGllfCPv[A/N7N or _MTjD#aXkQMF_>wrjmQfHmJzg9OlpCvlpg"FW8("xxhdQkeWiBt!RccGxqB`fDyO - These are not recent or old passwords of my account, that are randomly generated strings to symbolize the complexity)

Login is working fine, on every device, just the confirmation for the "cancel subscription" function is only working when you use less complec passwords... (such as: The$%cake%%is$%4%%L1e .- again, not a recent or old password of mine).

Is there a max. lengh only affecting the cancel subscription function?