Why is copilot so unreliable?

Do you guys use copilot and do you find it to be reliable? I impulsively purchased the pro version of copilot connected to my Microsoft365 business account and I deply regret it. It was very expensive, I paid almost 500 Euro including taxes and i was forced to pay for one year in advance with no trial period. Now, each time I ask a question or to generate content is rather slow and very hit or miss. I don’t have exact statistics but approximately 50% of the times I get an error or something like “sorry, I can’t help you right now”. I end up going on the free openAI page which seems to be much faster and more reliable. Does anyone have a similar experience?