Google Colab's compute units are evaporating periodically!
Hello,I am using Google Colab and the available computing units that I had purchased and accumulated while subscribing in the past are being removed by Google over time after I stopped subscribing. Why is that?For my instance, a few months ago,  I stopped my monthly subscription(adding 100 compute units monthly) of Google Colab which I had subscribed to for a long time. At that time, I had about 340 compute units remaining. About a month later I found my compute units became 300 exactly, and then  I used for short time and it became 293 compute units. And after that, some weeks later it became 200(!), and I use it a little then 19x, and then it also became 100(!), then it became 99 the, now it will be zero. And I also have another my account, paid colab, which has become zero units already.Google Colab is removing my ‘paid’ compute unit, if sometime later periodically.I already asked the local service branch of Google, but they told me I should ask to Google Head Quarters in USA.It would be greatly appreciated if you could explain why google do this way. I’ve lost the compute units that I paid.And even if this is actual Google’s policy, there need a proper reason. What do you think?Yours sincerely,
2024-06-29T09:02:24Z
Self reply, There exist expire condition. So this is removing periodically. OK, but I hope the expire date condition to be repealed or prolonged.