Fatale error in formatting.php

Hello guys, I bought Enfold theme and I’m pretty happy with it. Everything worked fine till today, when editing my homepage I’ got this error : Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 23417 bytes) in /home/bergamol/public_html/wp-includes/formatting.php on line 4221

It never happened before, and I get that error only when updating the home page of the italian version of my site. I don’t have any problems editing other pages of my site. I contacted my hosting and they increased the memory limit of my site, but it didn’t resolve the problem. Any idea how this happened and how to fix it? Thank you guys very much for your support.