It seem that missing translation file. Please copy manually file templates/ot_fashionpurestyle/language/en-GB/en-GB.tpl_ot_fashionpurestyle.ini into folder language/en-GB/.
Also copy 2 files:
templates/ot_fashionpurestyle/language/en-GB/en-GB.tpl_ot_fashionpurestyle.ini and
templates/ot_fashionpurestyle/language/en-GB/en-GB.tpl_ot_fashionpurestyle.sys.ini to
/administrator/language/en-GB/
Or you can try re-install the template via extension manager(the template only, not demo package).
After that, you may need clear all cache in backend.
Thanks