Let us know what they say, we dont know what they mean by database overload? Maybe you have a IO limit on your hosting plan or a database limit of some kind.
We need more details please, thanks :)
-high traffic per account up to 3000 unique visitor per day
-overusing query database
-overload data from database when opening webpage
-not using cache system/plugin for reducing database query
-using persistent mode when connecting to database
-using one or more statistic type script/plugin for collecting data such as visitor, counter, etc
-spamming into database in high volume, ie comments
-programming error
honestly im not quite understand myself. however, after they unlock my account, I saw several new members in my site and so many posting and comment from them. Unfortunately I forgot to take a note for the post timestamp
https://developers.oxwall.com/store/item/1279
As far as the other items, unless we have a specific reason, error message, or something to go on we cant assist you, the options are just too many.
However you must have a very strange hosting company because most hosting companies will tell you exactly what the issue is. Plus Oxwall is running around the world on all kinds of hosting companies and running very well. So i would tend to blame your host more than i would Oxwall at this point. Maybe you need to change hosts.