Your reasoning does not add up

So i went in for MAJOR surgery end of March. I had to go for a lot of physio but my claims submitted for this were (rightfully) rejected as i had run out of funds in my Savings. Up to there i get and understand. THEN Discovery realise they made a mistake on my Savings account (without even so much as a letter of apology) and paid money back into my Savings. I then asked well why cant you pay me for the physio's of the 20/4 and 15/4 as it was actually your fault that i paid for these out of my pocket - no we cant do that. But why? I dont understand. I pay money out my pocket because you made the error. You rejected the claims with code 276 which means no money in your Savings, which was right at the time, but now that you realised your mistake and put the money back into my Savings i expect these two claims to be paid as there is actually money in the Savings. You cant reject saying there is no money in the savings and then when there is money in the Savings you say you still cant pay them - and i still dont know why.