You are not mentioning the exchange app you are using, so how can we know if it is a reliable one or not?
Secondly, you might also have made some mistake knowingly, maybe while sending to the wrong address or network, you might have omitted it as well from the address.
You don't have to bring in the use of Trust Wallet together with an exchange here, I will recommend these few exchanges to consider.
Gate.io
Bybit
Binance but you can't make p2p on it.
Note that all these are KYC exchanges and if you want the ones that do not require KYC, here are some.
Bisq
Hodl Hodl
Failing to have mentioned the name of the local app OP used, to me means that there's no local app in this country I can trust to transact with because they are very well monitored, have unstable service, support and even network and they could be run or overtaken by scammers or hackers at any instance and that leaves the user exposed to such kind of risk.
Although Binance don't trade USDT or Binance to Naira directly, you can always use it along side another exchange you trust by sending from Binance to the exchange that trades P2P to Naira directly to your account. That's after sending from your wallet there, but be careful not to leave your funds on the Binance app for long or any exchange for that matter.