pending authorizations are an indicator that your client is buggy.
There are a lot of opportunities why you see that error message and why you don't find pending authorizations.
Simple sample: Your client creates parallel orders at 15:00 - a lot of domains per server, more then one server. 10 server, every with 30 new orders -> the next order has that error message. 30 seconds later, all certificates are created -> no pending order is visible.
So: How many servers use that buggy client? How many domains per server?
Is the same account used with such wrong parallel orders?
A correct client has always only one open order, not 2, not 5, not 200. Then the order is finished, valid + certificate or invalid -> next order.
Then you have never that problem of pending authorizations.
it would be helpful if we have an option to view our pending Authz associated with an account so that debugging such issues will be easy/transparent for LE users
Thanks for pointing this out. It's actually the case that a successful validation adds 30 days to the lifetime of the pending authorization, which is 7 days. However, this is definitely confusing. I'll talk to the team about changing it so valid authorizations always last exactly 30 days from the time of validation.
I looked in our logs for the authorization object you mentioned, and it appears that your client doesn't send a specific User-Agent header identifying itself, but instead sends a generic Java User-Agent. Could you fix that so it sends a User-Agent header indicating the client name and version?
In terms of the pending authorization problem: As @JuergenAuer said, this issue is usually caused by a buggy client. Since your client is not publicly available, it's hard for us to help you debug it.
Since the Let's Debug Clear Authz Toolkit couldn't find any pending authorizations in your logs, it sounds like you might not be logging every authorization you create. Can you double-check how many authorizations your code has attempted to create? If there's a mismatch, that is where you should concentrate your debugging energy.