It seems to me, that the grid bot will buy the whole amount and not the difference. If I choose a lower amount, I can choose to buy the difference.
My solution, I stopped the bot sold all sui manually and started the bot. Everything was ok. The total SUI amount was bought and bot started correctly.
Charlotte on Telegram experiences the same problem with her grid bots, she uses Bybit. So I think somewhere a bug in the grid bots with the free balance.
It seems to me, that 13 SUI is not enough to cover the USDC. (13 * approx.5 = 85-90, diff USDC is 170 USDC).
We actualy have options to sell the base difference to conver quote asset. In your screenshot it doesn’t work, because wont be enough quote.
But I need around 65 (13*5) USDC to buy the SUI. And I have 170 USDC free. That’s enough in my eyes. I my eyes, I needed to get the question if I want to convert my USDC in the remaining 13 SUI.