localization problem

i cannot translate thisto Greek

i followed this guide
https://yithemes.com/docs-plugins/yith-woocommerce-request-a-quote/04-localization.html

the po and mo are uploaded to /htdocs/wp-content/plugins/yith-woocommerce-request-a-quote/languages

yith-woocommerce-request-a-quote-el_EL.po
yith-woocommerce-request-a-quote-el_EL.mo

my main wordress language in wordpress is Greek
and i changed to the main wordpress theme with no luck

im doing something wrong

https://wordpress.org/plugins/yith-woocommerce-request-a-quote/