Changing tamagotchi Angel batteries

I have recently started trying to collect tamagotchi and bought a tamagotchi angel English version on ebay. It included  new batteries in the envelope. I have tried to put them in however the device is only working for a few seconds after I press the reset button on the back and it beeps. After I reset the clock it shows the ufo of the previous tamagotchi but keeps switching itself off before I can trigger the next egg to show up (or whatever the angel does to be born). I'm trying to figure out if this is something wrong I'm doing or if I've been sold defective product. Because one would mean I just gotta do something different and the other means asking for a refund. Please help. Thanks

So turns out the batteries were bad I got it working 

The Tamagotchi Angel's "egg" sequence is the death sequence of a standard Tamagotchi - so it appears as a ghost on the Japanese version, or a UFO on the English version, before being born. Since it's a vintage device, it doesn't retain data from previous runs, like the Tamagotchi Connection devices and later do.

The resetting problem may be due to the battery contacts being flattened due to long-term use by the previous owner(s). The first thing that I do when I've purchased a used or new-old-stock virtual pet is to take a very tiny flat-head screwdriver, and use it to VERY carefully bend the contacts upwards a little, and this usually fixes this issue (this isn't something that most sellers realise can be an issue).

If it's not that, then I would try a different set of batteries, since even unused ones have a shelf-life.

EDIT: Haha, beaten to it! I'm glad that you got it sorted out!