Assistant making up phone number

I created an assistant with file search on and a vector store with a .txt file attached.

The attached file contained information about a company, and the assistant is meant to be a QA bot. However, after some testing, I noticed that when I ask for the company’s phone number, it returns a made-up number.

In info.txt:

For more information, you can contact us by sending an email to info@bo*******com or calling +54 11 ****-1639 from Monday to Friday

But when I asked (via API):

I want to make a claim

The response of the assistant was:

To make a claim, you can contact us through the following telephone number: +54 11 5263-7400. You can also send an email to info@bo*******com. We are here to help you.

As you can see, the email is right, but the phone number is not; the assistant invented it. This doesn’t happen every time; sometimes the bot responds with the correct phone number.

I need to fix this, how can i make it respond correctly without messing up with the phone numbers?