Make sure you have the WPFunnels license activated and it is not expired. Then follow the steps below.
Step 1:
Go to WPFunnels > License and click on Deactivate License.

Step 2:
Then, go to the Plugins tab and deactivate WPFunnels Pro.
Step 3:
Next, go to WPFunnels > Settings, move on to Advanced Settings and click on “Delete Transients”.

Step 4:
Then clear the browser and plugin cache.
Step 5:
Now, activate the plugins and activate the license key.
Clear the cache again.
Once you have done this, check after a couple of minutes and you should be getting the update option.