If you insert a block, AutoCAD will first look at the block definition in the drawing. If the block definition doesn't exist in the drawing, it will insert it from the directory of electrical. So probably there is an old definition in the drawing. Do an swap/update block -> update block. Then select the block. It will probably ask for the location of the new block which probably is Lib\panel.
Alternatively, delete all those terminal strip blocks. Type purge and purge that terminal strip block. Then insert it again.
If you already did this and it didn't work, attach the drawing so the people here can take a look at it
Sven Kloeck
Electrical Network Design