As already explained in the title, blocks don't get placed when switching them in the hotbar by using the mouse wheel to do so while jump bridging; you fall down in that case. However, when switching the blocks via the keyboard keys, it works. I experienced this issue while playing Sky Wars on The Hive, where one stack of blocks depleted, whereupon I had to switch to another one so that I could continue jump bridging.
We're tracking this issue at MCPE-25778, so I will resolve and link this report as a duplicate.
That report has already been resolved as Won't Fix, which means this is considered a bug but won't be fixed. Please do not leave a comment on the linked report.
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