maybe it's because the boat is not full above water, so lily pad can be placed. but the boat appears so it's destoryed. check if there's boat or block with functionality before place lily pad
MC-172703
Place lily pad and break instantly when right clicking boat in survival
Resolved
Duplicate
0
peterhunt
(Unassigned)
Confirmed
(Unassigned)
1.15.2
Retrieved
The underlying bug is MC-667 (which previously only covered placing inside players). Therefore I resolved this report as duplicate.