Every time you reinstall alby extension you need to re-enter your private key that could be the reason? at least that's what I noticed.
Discussion
Really? Weird, I thought they saved the key, but I guess it makes sense, it is safer that way. Welp.
Sorry for this experience. It also depends on the browser settings if data is available from local storage after a reinstall. If you could check if everything is working fine, that would be great. If you get any error message, let me know.