I've also read that one should not use an address twice. I have the following case and I would like to know if my tokens are potentially in danger. I have a seed with two generated addresses in total. For the first address, I once received IOTA. For the second address I received two transactions. So far I have not sent any IOTA with both addresses. So I used an address twice to receive tokens. Should I act or are my tokens safe?
You are safe, you can even receive even more on both addresses if you like. Only when you send IOTA now, you should generate a new address for receiving IOTA.