SDCard is out always, even though DJI says they fixed that. As long as you have "over 3 Gig" free in main memory (As listed in update) you should have zero issues. If you can't do it OTA like so many, then try Asst.2 for mavic (latest release.) See post above
Except disabling Wifi if your doing OTA obviously. Always remember if you try once and fail, you more often than not have to manually go in a clear cache or files, so after one fail the other 19 attempts were for nothing if you didn't bother to do that. Next is below to correct your errors if you don't have skill set to clear your own memory and cache. I suspect yours is a onboard memory error though just from prior posts.
IF it fails then,
factory reset (last resort) make sure you keep any files you want first (Sure you know that), If it fails after all of these it's a return.