Installing gearman

Hi,
I have installed gearman server, it went well. But when i try to configure gearman with PHP, it's not working. I am on ubuntu 16.04, running apache with php 7 using ispconfig 3.x
I configured global php.ini, cli.ini and website custom php.ini with gearman extensio.so

I get below error when i check the version of gearman from php echo.

PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib/php/20151012/gearman.so' - /usr/lib/php/20151012/gearman.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Fatal error: Uncaught Error: Call to undefined function gearman_version() in /home/ubuntu/gear_php/test.php:2
Stack trace:
#0 {main}
thrown in /home/ubuntu/gear_php/test.php on line 2


Please suggest if i am doing anything wrong.

 

Sorry for the late reply:
ls: cannot access '/usr/lib/php/20151012/gearman.so': No such file or directory
I get this when i run command.

 

Below is the screenshot of that directory, i don't see gearman.so in there/

 

Thanks, i have reinstalled everything, all is working fine now, but when i run php command i get following warning always.

PHP Warning: Module 'gearman' already loaded in Unknown on line 0

I have removed gearman extension from all php.ini but still, i see the warning.