I read an article saying that the bandwidth limits are set to hinder spammy type posting, etc. I post once, maybe twice a day and my posts usually only include one photo and not a lot of text. I am also not an excessive voter, maybe 10-12 per day. According to what I have read on all the comments here, my SP should be sufficient. I have been getting this message on and off since Saturday. It's a mystery.
Thank you for offering your help but in my limited understanding of how Steemit works, this seems like a problem larger than your generosity. I am encouraged by people like you willing to help. Keep up the good work.