Parallels Plesk Panel or Plesk is known as one of the most multi-functional Control Panels. It goes far beyond the capabilities of the regular web-based tools for managing the server resources your sites need to exist. The PHP limit in Plesk can be increased by following the below steps
Step 1: Log into the website hosting panel for your domain and select the Websites and Domains tab, then click on PHP Settings
Click PHP settings option
Step 2: Under Performance settings, you can increase both upload_max_filesize and post_max_size limits.
To adjust the maximum post size, enter a value into the select box by left-clicking first.
For example for 20 Megabytes enter “20M”, for 64 Megabytes enter “64M”.
Set the size limit
Step 3: Click OK to save.
Click OK to save