I purchased a coupon for an excursion in August of this year but I was unable to use it...

I purchased a coupon for an excursion in August of this year but I was unable to use it because I did not receive it. I provided an incorrect email address, but on the day we were scheduled to use the coupon I contacted you by phone - from a cruise ship in Alaskan waters at some serious cost to me. The agent indicated that he would work on the issue and I told him that time was short* I provided my phone number and correct email address but I did not receive a return call. It was not until **:** PM on September * that I received an email explaining the confusion about the email address and asking if my issue had been resolved. It had not and since the tour we had booked was on September *nd I paid $*** for another tour while we were in Ketchikan. The Groupon agent had my phone number and we could have easily resolved the issue during our telephone conversation on September *, but they did not respond to me until the tour date had passed.