What I wanted to ask is whether the user can send two transactions with a value lower than the minimum, which in total is higher. In this case, the mixing is done in the same way.
I think we all understood you well. One transaction, where the minimum is 0.001btc is correct. Everything else is considered a donation to the mixer.
This is very clearly emphasized in the mixing process, so there really shouldn't be any confusion
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The address is valid for 24 hours. Minimum possible amount for this address: 0.001 BTC, maximum amount: 983.15215706 BTC. Use the address only once.
For example, in case you have an amount of 0.0009BTC in two different wallets, the best(only) option is to first consolidate and combine them into one wallet and after that send as much as you want to the mixer.