In some cases, after theme update, you can face the issue when a few lines, that are not translated - appear on your website or words that have been translated before - remain back in English. Very likely this happens because, while theme update the developers added new lines or changed the old ones. In this case, you need to update your translation files. For this you will need:
Unzip theme package on your local computer, copy your .po file into the folder with theme.
We will show that on Legenda as an example. But, keep in mind that the process is similar for all our WordPress themes.
Open it in Poedit, click Update button and updating catalogue process begins.
Then you will get the window with the list of lines that were found in the sources but were not in the catalog. Press ОK button and new lines will be added. Now, look through if all the necessary words and sentences are translated correctly. Translate again if necessary. Save your file, it will generate both .po and .mo file for your translation. Place them into languages folder /wp-content/themes/legenda/languages instead of an existed ones. Check your frontend for correct translation occurrence.