I've experienced this in all versions since I recently bought my hardware, so 1.17.0 and up. It certainly may exist in previous versions as well.

I am using a Galaxy Tab A 8", Android version 10, up to date as of this post. Minecraft (Bedrock) is also up to date with the Play store. I own four (4) USB dongles that allow use of my Microsoft wireless mouse and keyboard. No other applications exhibit any operational problems.

In Minecraft, this hardware works well the majority of the time playing. However, if I attempt to use chat (T or Enter) or a command ( / ), this action consistently-every single time-breaks proper keyboard control. It's as if the first keydown event is respected, but not the keyup. For example: after chat, I walk forward then release the key. My character continues to walk. If I press back, he will stop, but then he is stuck. Forward and back are now broken. The same behavior occurs for left and right. Jumping seems fine. Going to inventory will temporarily enable me to walk again, exactly one time; then the problem will return.

The way I've found to address the problem is to pass peripheral control back to the operating system; that is, get back to the desktop, or press the Windows key. Google Assistant pops up, then I hit back to get back in game. Now, all is working fine again... until I attempt to chat or use a command. This is 100% consistent, easily reproducable across all four of my USB dongles. Again, no other app I'm aware of exhibits this behavior.

One other thing to note: there is at least one condition where this problem occurs which I have not managed to isolate. I will be playing and then unexpectedly, I continue to walk forward (sometimes fatally). I believe it might have something to do with rapid mouse clicking (as in attack) or perhaps upon holding the mouse down (as in mining) while using the keyboard, but reproducing this method consistently has been unsuccessful.

Thanks for listening. I hope we can figure this one out.