i had the same make 2 days ago and they taste totally differant why is this?

There are many reasons for what is known as bottle variation.

1) Storage issues. If one of your bottles was improperly stored such as with too much heat exposure, or the cork allowed air to leak, then the taste may be off. You didn't mention whether one of the bottles actually tasted bad.

2) Cork taint. A really common problem in the wine industry. A chemical called TCA sometimes contaminates the cork at the winery, and this can cause the wine to have muted fruit flavours and aromas and can give the wine a musty, wet cardboard smell.

3) If you just bought the wine and it was heavily agitated during transport, the wine may be in what is known as "bottle shock." This can happen whenever the wine has been agitated or immediately after bottling. Check to see if the store you bought it from just took delivery within the last week or so. It takes a few weeks for bottle shock to settle.

4) Variation between vintages. You said it was the same brand, but see if they are the same year. Much can change in a wine from year to year depending on the quality of grapes grown that year.

I hope that helps.

Cheers!