Sorry that happened to you. I have not shot with the GH5, but consistently had the same problem with the Panasonic G7 and that same Lexar card (mine was 1000x). As soon as I switched cards-- over a year ago-- I have not had the problem. There were other G7 users who had the same problem with that Lexar card and they have reported that the problem was resolved when they switched cards. I did not try to retrieve the info on the card as it was not critical, so I can't help you with that one. Hope this helps and sorry again for your problem.
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