This problem has been reported before and resolved but it does not apear to be fixed. The problem is that slimeblockes on pistons are no longer launching entitys.
MCPE-92114
Slime block is not working
Resolved
Duplicate
0
Matthew Crooker
(Unassigned)
Unconfirmed
Amazon
fireos 7.3.1.4
1.16.1
Retrieved
Thank you for your report!
We're actually already tracking this issue at MCPE-62419, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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