HAMMER GPS - NEW CHANGES

I have been using Hammer GPS for the past two years and have been very happy with it. Recently Hammer has had to begin charging a small fee for the usage. I dont have a problem with the charges, however I am having a problem with my Debit/Visa not being accepted as a payment source. I have been in contact with Hammer and they suggested the problem lay with my iOS software. That is almost true, there is a problem, except that I am on Samsung/Android. I have been trying to find a work-around, but with no success. Is there a way around this problem, short of changing from Android to iOS?

thanks in advance!
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