This article describes the known issue with en_GB locale (UK) being removed from Manage Recruiting Languages when making any changes in Manage Languages or any configuration changes in Provisioning > Company Settings.
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SAP SuccessFactors Recruiting Management
The Recruiting module is making used of a deprecated database entry for pulling locale information, hence indirectly causing some languages to be removed from Admin Center > Manage Recruiting Languages when there are any changes in Manage Languages or any configuration changes in Provisioning > Company Settings.
This issue was fixed in RCM-76879 along with the ongoing effort in the same Engineering request that other languages initially not supported by SuccessFactors be eventually supported.
The en_GB locale issue is fixed in b2205 release.
3156917 - Recruiting Support for other Languages (e.g., Lithuanian, Estonian, Latvian) - Recruiting Management
3028684 - Lithuanian (li_LT) language support for Recruiting - Recruiting Management
2979418 - How to add Lithuanian as a language option in SuccessFactors (Platform)
Implementation Guide - Full List of Supported SAP SuccessFactors Languages and Locales (Platform)
English UK, Language Support, en_GB, Manage Languages, Manage Recruiting Languages, Removed, Not Available, Recruiting, RCM, Other Languages, Locales, Known Issue, Known Error , KBA , LOD-SF-RCM-ADM , Admin Center, RBP, Permissions and Settings , Problem