My driving instructor?

I started my driving lessons about 3 or 4 weeks ago and pre paid for 5 hours of lessons so far i have taken 3 and a half hour but litrually and hour before my second lesson my instrcutor canceled due to being ill witch i was like ok people get ill and rearanged it my sister-in-law who is with the same instructor had a lesson a few days later but she didnt cancel she just didnt bother showing up! i got my second lesson on sunday and we aranged for my 3rd lesson to be this Friday but yesterday i got a message from her saying she had to cancel because something had come up and asked me when i was available next week, i have messaged her telling her but have had no reply, i don't know what to do because when i am actually driving she is a good instructor but i'm really nervous driving at the moment and it sort of makes me feel worse that she's canceling and feels like she is not making effort atall! what should i do.. and if i get rid of my instructor how should i do it !