Somali language could not find

Hello,

Please read: https://polylang.pro/doc/configure-the-languages/#add-language.

Somali is not in our predefined list, because the WordPress translation never reached a sufficient level to release a translation package. The current state is only 34%. See https://translate.www.ads-software.com/locale/so/.

However, as explained in the doc I linked to above, you can create it easily.