I borrowed my sister in laws samsung i70 now it is

Shut the camera power off, and remove the memory card.

Observe the label side of the card and find a small plastic tab on the left edge of the card. Slide the tab forward (towards the connector end) into the "Unlocked" position.

*Carefully* reinsert the card into the camera - taking extra care to slide it straight in - so that the tab is not bumped back to the "Locked" position.

Power up and and take pictures.

If it doesn't work - it is possible that the tab got moved during the reinsertion process. Remove the card again, and place a *small* amount of scotch tape over the tab to keep it from moving, and try again.

Good luck!