¿Cómo se llama tu maestro de español?
Mi maestra se llama es Señora Johnston.
Mi maestra se llama es Maestra Johnston.
se llama = her name IS
if you also add "es" it is like stuttering = her name is IS
For politeness sake, when talking about Sra Johnson, it is nice to add the honorific (just for politeness) LA Señora Johnston
Sra