I would like to check that how to increase the count of 50 in the Trigger Phrases. Is it something subscription need to be purchased or is it limitation. If the Knowledge base need to be increased, what other suggestions can be provided.
Thank you!
Generally, a PVA topic would only have 5-10 trigger phrases, as a topic is intended to handle a single user intent (book a flight, ask for help, etc). 50 would imply you're either trying to tune the language model very precisely, or that you're trying to cover multiple user intents with a single topic.
If it's the latter, the best case would be to use separate topics for different questions vs putting them all in one topic. One exception is the fallback topic, where you might do a QnA lookup or other which could search over a corpus of questions and answers such as with Custom Question Answering service.