Creating Menu item - Coupon List give error

I've added a menu item "Coupon List" but when you click on it I get this error: Fatal error: Class AwoCouponController cannot extend from interface JController in /home/content/93/11223693/html/components/com_awocoupon/controller.php on line 21.

In addition I have a question about license. I didn't realize licenses expire after two weeks and we have to make it permanent (my customers coupons stopped working). I've purchased the pro version so why wouldn't the license be permanent? When i read how to make permanent:

Go to the "Licenses" screen
Click "Make Permanent License" under the license you want to make permanent

I do not see Make Permanent, i have these fields:

Website
License
Local Key

I am running joomla 3 with hikashop business vers.

Thanks.

Hello,

One note, the license does not affect front end function. If your license expires and you still have valid coupon codes in AwoCoupon, they can still be used on the front end.

Yes your license is already permanent. When following the instructions:
https://awodev.com/documentation/frequently-asked-questions#license-permanent

You probably forgot the very last step:
*******IMPORTANT LAST STEP******* Copy the generated Local Key from AwoDev.com into your Awo Software

So you just need to verify your local key in your account matches the local key in AwoCoupon, if not update it.

For the error, I have sent you a private message with the fix, its just too much to post in the forum.