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I found a document might help you.
Explore & Configure Deep Links to Apps - Teams | Microsoft Learn
My theory is you are copying the link from a personal tab, paste it in another tab, it will lose the context since the scope is different.
My suggestion is formatting your deep link the structure like the picture above (adding context and channel ID)
I also test in my own environment, sometimes the deep link can load the app and sometimes don't.
I have to reload 2-3 times for the app to load correctly.
I hope this information helps.
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