My temporary solution
I also had this problem. I remember that I had no problems in March before, so I found the March version of uplay (uplay 104.0.7325.0). I installed it again,and it worked out smoothly, but it was a temporary solution. It would not be a good experience to keep offline and the previous version. If you mind, don't do it.
This is my solution
1: Before opening the previous version, you need to disconnect the network to prevent automatic update of the version until the login interface appears, and then log in online.
2: After logging in, keep online, run the game once and exit, and then disconnect the network in advance to prevent the update detection of offline restart later. Then click the icon in the upper left corner to select to let uplay enter offline mode. After restarting, the game should be able to use normally.
OK

PS: before starting an uplay, you must disconnect the network and then enter offline mode to prevent version problems,It's a headache,I hope this bug can be fixed as soon as possible.My mother tongue is not English,and my English is bad,Hope you can understand.
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