No, SiteSpeakAI does not limit the number of questions a visitor can ask. We do rate limit questions to 5 questions per minute.
From the blog
Custom model training and fine-tuning for GPT-3.5 Turbo
Today OpenAI announced that businesses and developers can now fine-tune GPT-3.5 Turbo using their own data. Find out how you can create a custom tuned model trained on your own data.
Automate your customer support and marketing with Zapier and SiteSpeakAI
With the power of Zapier's 6000+ available apps and integrations, you can now connect your chatbot to your favorite tools and completely automate every aspect of your customer support and brand marketing.