Hello @Martano, Giovanni ,
Thanks for the question and using MS Q&A platform.
Seems like you have already reached out in SDK GitHub platform for this issue and one of our engineers have suggested the workarounds to overcome it. I'm sharing the link here as it can be beneficial to other community members who reads this thread.
Here is the GitHub link where this issue has been discussed with possible solutions - [BUG] Send message to service bus using ServiceBusSenderClient get timeout]1
Thank you
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