Encrypted Time Machine HDD fails to auto-mount after sleep on Mac Studio

I bought an M2 Max Studio (now Sequoia 15.6.1) over a year ago, have a 4TB SSD for my media files (no issues) and a 14TB HDD external for Time Machine. This HDD has never Auto-mounted coming out of sleep when encrypted - I mount daily my Time Machine HDD daily with Disk Utility. I have since tried reformatting and using unencrypted Time Machine on the (reformatted) unencrypted HDD and my Studio has no issue auto-mounting the HDD/Time Machine coming out of sleep.

I have spent hours researching how I can get my encrypted HDD to auto-mount out of sleep, but nothing works. The issue of manually mounting is sometimes I may realize after 1-2 weeks I have not been mounting my HDD whereas my goal is for hourly backups always. I've tried exploring keychain issues, reconnecting / new cords, re-formatting, etc... but always the same result. The HDD is always visible in Disk Utility and will mount automatically after a hard start, but never when coming out of sleep, while encrypted. What am I missing?

[Re-Titled by Moderator]

Original Title: External Encrypted AFPS HDD dedicated to Time Machine will not auto-mount out of sleep - Studio