after installing ssl certificate ...paypal express checkout doesn't work

after installing ssl certificate my websiste is now on https protocol and in my OC 3.0.2 doesn't work anymore paypal express checkout.
When I click on checkout button to end order, this button change in loading and stopped there, so it doesn't charge popup of paypal express checkout ; this happens with a quick one page checkout extension.
Then I disable this extension (quick one page checkout) and try with default checkout module and in step 6 (confirm order) I have on screen this message:
Fatal error: Uncaught exception 'Exception' with message 'Error: Unknown column 'weight' in 'field list'<br />Error No: 1054 ....... in /public_html/system/library/db/mysqli.php on line 40

ANY SUGGESTIONS?
HELP

Saying you don't have a weight column what other extensions do you have installed? Did you refresh the modification cache?

on line 40 the code is:
throw new \Exception('Error: ' . $this->connection->error . '<br />Error No: ' . $this->connection->errno . '<br />' . $sql);

"Saying you don't have a weight column what other extensions do you have installed?"
Could you explain me better and how to find solution,I have no idea

I have click on clear and then on refresh in modifications but problem (fatal error message) persists...

I have found extension that make conflict, now I contact developer. Thanks for suggestion