Hi Paz,
I see that you are running the current version of The Events Calendar, but your version of Events Calendar Pro (4.4.5) is a bit outdated – the current version is 4.4.24.2. So, this could indeed be the cause of the 404s, and updating might solve the issue. However, I would also recommend running through the steps outlined here. TheseĀ typically resolve 404s, but if there is an incompatibility issue between the two versions that you’re running, then would need to update.
I would also recommend running through these steps to test for conflicts between your theme and other plugins.
We are not able to provide technical support here in the Pre-Sales forum, but if you do renew your license and are still running into this issue after updating Pro, then please let us know over in our Events Calendar Pro support forum. We’ll be happy to help you out with this over there!
Thanks,
Jennifer