The logs show that you are working with a wifi network called UPC45183D3, and two access points correspond to that name.
One of them reports reason code 19 when you try to connect. This access point is reporting that it is running at capacity and is unable to handle any more connections.
The other one reports reason code 2, which is again a case of the access point refusing to service the connection, but without a very clear reason.
Do you have any unrelated wifi networks that you can try connecting to when you encounter this problem? Such as a hotspot connection on your smartphone. Just to confirm if your computer is able to successfully connect to other networks at such times.
As a separate test, when you encounter these connection difficulties, do you have any other devices that you can use (excluding any that are already connected to the same wifi network) that you can use to double check the ability to connect other devices to the same network as a side-by-side test right at the same time?