I'm using Kubuntu 18.04,
I had this same issue before. I noticed that, when ever I try to connect by WiFI it asks for the KDE Wallet password, and also had the same issue in getting connected with GoogleDrive. Then, I re-installed OS and I didn't see the KDE Wallet when connecting with Wi-Fi; GDrive also connected OK.
After reinstallation of Kubuntu 18.04, the problem returns.
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I have gone through this, but the problem didn't get solved.
