Unable to select signs for edit LockettePro v2.11.1 on Spigot 1.20.4

[mischi3f]

Server Version spigot-1.20.3 AND spigot-1.20.4

LockettePro Version LockettePro v2.11.1

Issue
When right clicking on sign, status message shows [LockettePro] Sign Selected however, sign shows on screen and is editable.

Regardless if changes are made (including escaping out), the status message [LockettePro] This block is already locked. is displayed and [ERROR] appears at the top of the sign.

Workaround
If you right click the sign again, and replace [ERROR] with [Private], the sign will save and work again.

Server Log on Load
[12:38:48] [Server thread/INFO]: [LockettePro] Enabling LockettePro v2.11.1
[12:38:48] [Server thread/INFO]: [LockettePro] Incompatible server version detected: 1.20.4 . Trying to run into 1.16 compatibility mode!
[12:38:48] [Server thread/INFO]: [LockettePro] ===================================

[woeterman94]

Same here