If the database was having an issue, everyone who uses Abrosia with the database setting would be having an issue.
How long are you spending in each shop? What shops? Some restock very slowly, some very fast. If it restocks slow, you might not see anything before you move. If you don't move at the right time, you may miss a quick shop restocking and the items are gone.
The shop may also just be full of crap items. That depends on the shop.
With user numbers decreasing, crap items stay longer because there aren't as many foolish people to buy them.
Also, do you happen to have Abrosia's automatic pricing turned on? If so, turn it off. It doesn't work, that may be causing the issue.
Do you have the buy items where profit must be greater than % of the item price on at the same time? That may be an issue. If something is 1k profit, but it's not the right % of the item price, it won't be bought.
Are you using a proxy at all? There may be an issue with it.
Is the AAA on? Turn it off, it doesn't work.
Have you tried a fresh install of the manager? Uninstall the manager completely, redownload it and reinstall it.
Did you choose the five finger discount boon from the weekly obelisk? That doesn't work at all with Abrosia, you won't be able to use it until the boon wears off.
Mine is working just fine.