Fandom Token purchased from Probit Global as USDT,
is it better to change it to USDT when fandom Token grows?
Yes it's better to change it to USDT to secure your position and then you should wait for the correction to happen. You can use your profit to enter in the market again. You can save some tokens for long term like if you're think that's good to keep some in your wallet.
Or is it better to buy more fandom when USDT grows?
That depends on your analyzation. if you're thinking that's a good project, you can buy more otherwise when it doesn't have bright future and just convert it into USDT and then you can wait until it will be dumped again to the bottom. You can re-buy your fandom token again.
Please give me some advice.
Please, do your own research first before try to take any suggestion or advice from others.