I'm playing with german client there is "Blitzschlag" (lightning bolt) and "Blitzschlag" (bow dropped by Asaad) essentially the same word for the spell and the item.

I have been using a macro (simplified)

#showtooltip
/castsequence Blitzschlag, Blitzschlag

to cast lightning bolts but since I looted that darn bow the macro stopped working. I realized the problem with the conflicting item and sold the bow but the macro wont work. Hotbar tooltip still shows the bow if a lightning bow is in order. I already deleted my cache and disabled all addons but the problem remains.