Drobo reformats every time I add a drive

So I have a version 1 drobo, Dashboard 1.8.4, firmware 1.3.8.
I plugged in a 500gb drive, and the drobo recognized it, and I formatted it for 16tb. I put some test data on it, then added a 1tb drive. The drobo recognized the 1tb drive, but at the cost of the volume I had created. After the drobo had spent an hour protecting data, it came back saying that there were no volumes. I logged off, switched off then on again, waited an hour, but no luck. I reformatted, and then added some test data before plugging in a 1.5tb drive -the same thing happened. Even if I removed the new drive, and put the old two back in I could not get it to recognize my old volume.
Is this normal, or do I have a defective unit?
I’m using Lion on an MBP.

That is not normal - but i cannot advise what maybe happening

when you had the 500gb drive with a volume and daata on it - you plugged in a 1tb drive with drobo running and your volume you had previously created immediately dissapeared without you doing anythign else - is that correct?

Yep - it disappeared, both drives started flashing green / yellow, for about an hour, and it said ‘protecting’ and then it came up saying ok, but no volumes, asking me to format a volume.

thats very strange for a couple of reasons

telephone support is th eonly advice i can give, that should not be happening

Thanks - I’m out of warranty - will telephone support help me?

probably - you wont get hardware replacement but you may get some advice?

Thanks I’ll try that.