Create 318Jr 10-15-20M Tri-bander

Early this year, I replaced the driven element trap coils (10/15M)of the Create 318jr tri-bander becasue of high SWR. Today I have the same problem again, so I start to check what happen inside and root out problem sources.
The 10M trap looks fine:

However, the 15M trap coil spacing is not in equal spacing, so I removed the winding and found the coil form was melted.


I need to find suitable time and method to fix it. For the time being, running QRP with the Fritzel vertical.