Hello,
I have just read your job description carefully, this type of errors occur because some of the functions that work on PHP 5.x have been removed in PHP 7.x.x
To fix the error, someone should modify manually the functions that may occur an error.
I have an excellent background in web development and have been doing this for 9 years.
Highly skilled with debugging and I have considerable experience in PHP.
So I am confident in this project and believe that we would be a great fit to work together.
Let me know what times are convenient for you so we can discuss the details further.
I am available just about any time you need me to work and look forward to working with you.
Thanks, and best regards,
Enrique v.