php post content-length exceeds - post_max_size

1) If you have access to the php.ini file there is a easy fix, just edit the post_max_size line with a higher value you want.

2) If you do not have access to the php.ini file you can create a text file and name it as php.ini (remember to check if the file extension is .ini not .txt) and put this line inside:
post_max_size = 15M
save and upload to the folder where your php script is placed.

(I have used 15M, you can put any value you want)

It is also better to have a chat with your hosting technical help team.