We look after our neighbours mobile phone and top up every 3 months. I put 20TL credit on the mobi in January, the pre top up balance was -4.5TL, so when the top up was completed the balance was 15.5TL.Today I went to put 20TL credit on the phone as our neighbours are due to arrive tonight. When the credit went on, the balance was showing as 15.5TL. I queried this with an English speaking Turkcell Customer service operator. I was told that the credit had gone on in January, and was then transfered to another mobi number bringing the balance back down to -4.5TL.I do not know how this was done as the mobi was switched off after the credit was put on.I can only assume that the shop that put it on, transfered it to the other number.I am wondering if this has happened to anyone else.