plugin wont drop gift into cart

I created a rule for free gifts over 299. Tested, worked well. Out of the blue client called to say it stopped working. They get modal, but “add gift” does nothing, modal keeps re-appearing. Im in the middle of a promotion… Any clues as to what may cause this …. see video https://www.screencast.com/t/m2EudRTIuKRH

If going pro will solve this, happy to do so …. I need know if pro will have same problem, and also if pro can handle multiple rules.. so over $199 gives them option for product#1 and over $299 given them option for product #2 …. please confirm THanks !!

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