On-device setting accept at most 31 characters

I'm developing on-device setting. Now I use on-device setting to input the weather key which is 32-bit string. When I input it and can only input 31 bits. The 32th bit is trimmed.

When I input the characters on watch, it popup a input dialog box on the "GARMIN CONNECT" app on my phone, and I can input at most 32-bit string. But after save, the last one is trimmbed.

So I can only input at most 31-bit string on on-device setting. I thinks it's a bug. Almost weather key is 32-bit string after all.