The wallet is closed source, so the support team is the only one who can explain to you the cause of the problem and how to solve it. you must trust that they must be good enough to close any bug, and in my opinion it is a risk that I do not advise anyone to take it.
According to troubleshooting answer If the amount of an UTXO is smaller than the partial fee needed to send it, that UTXO cannot be sent (with current fee level).
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If the amount of an UTXO is smaller than the partial fee needed to send it, that UTXO cannot be sent (with current fee level). If all UTXOs are dust, nothing can be sent from the account.
For example, a Bitcoin address may contain 3 UTXOs, of the amounts: 0.0090, 0.0003, and 0.0004, for a combined balance of 0.0097. Assuming a current byte fee rate of 50 satoshis/byte, and number of bytes for one extra UTXO as 110, the extra fee for an additional UTXO is 0,0005500 (50x110 sats). This is higher than the last two UTXOs, so those are not possible to send. Only the 0.0090 UTXO can be sent – in full or partially.
For example, a Bitcoin address may contain 3 UTXOs, of the amounts: 0.0090, 0.0003, and 0.0004, for a combined balance of 0.0097. Assuming a current byte fee rate of 50 satoshis/byte, and number of bytes for one extra UTXO as 110, the extra fee for an additional UTXO is 0,0005500 (50x110 sats). This is higher than the last two UTXOs, so those are not possible to send. Only the 0.0090 UTXO can be sent – in full or partially.
Source https://community.trustwallet.com/t/unable-to-send-due-to-dust-error/1188
and the solutions they propose
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What can I do?
- Do not send very small transactions with a high fee. Since the network will attempt to create a UTXO from a small transaction, the transaction will fail.
- Send what is possible using Max Amount, with default fee setting. This will leave the small UTXOs, but send out the non-dust ones.
- If nothing more can be sent with default fee setting (only dust UTXOs exist), try sending with lowered fee. You can adjust the fee 6.6k from the transaction confirmation screen. Warning: with low fee a transaction will take longer, sometimes even multiple days!
Useless solutions indicate extreme laziness.
