I have changed hardware several times, Followed by clearing license in cp.sambapos.com but have never faced this issue. Had it been about clearing license keys in the licensing portal other users would not have faced it as well.
Also, my reseller has confirmed me by mail that the issue was because of the expired android licenses.
they have cleared the expired licenses for android mobile client and i was able to apply the license now.
For your reference attached is the confirmation reply
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