bad experience.
We had a major problem with this tour guide agency. We ordered a tour of the communism museum in prague online. Then, we received an email from them telling us they were too busy for the date and time we initially chose. It was in the morning. They asked to re schedule the tour for the afternoon or the following day. So, we instantly answered that we were ok to re schedule the tour for the afternoon of the same day. Then, 17 minutes after the initial date and time that was planned, we were told that we didn't come to the meeting point. However, as I said before they obviously cancelled it. We opened a dispute on Paypal.
Also, they told us we were unreachable by phone. However, I think I have added my phone with the international prefix. Also, I instantly receive notifications of emails on my phone. So, they could have sent an email and I would have answered it instantly.
Update: I received a refund but I don't know if it was initiated by Paypal or by the vendor.