Hi Dave
When exactly did you complete? It appears that some of those paying AEA their community fees by direct debit have mentioned before that the debit is listed as El Hacho. If you have completed fairly recently, then you would have paid a one off 300 Euro "sinking fund" payment into the community and then there will be an apportionment of the quarterly community fees, depending on when you completed. Fees are due/paid every three months from January. So, say, if you completed beginning of May, you would have to pay the 300 into the fund, plus whatever your quarterly fees are (for a two bed approximately 350 euros more or less) apportioned for May and June. The next payment will be due by approx. beginning of July.
Maybe this is what the payment is, the apportioned quarterly fees (if you haven't already paid them, that is!!).