Safe to reheat tinned tuna?

[WDWU1802]

Sorry if this is a silly question, grew up veggie so lacking experience in the seafood prep department!

I'm planning to cobble together a lunch using some ingredients I've found raiding the back of the fridge/cupboard: tinned tomatoes, onion, pepper, aubergine, puy lentils, cheese - and, to bulk it out a bit, a couple of tins of tuna. Dump it all in a pot, heat it up, Bob's yer uncle.

Can I safely reheat any leftovers in the microwave for tomorrow's lunch, or is that a nono?

Yes of course

Yes it's fine

Refrigerate the leftovers as soon as they have cooled, and they will be fine in the fridge for three days if necessary.
I live alone and often make a large fish and seafood paella or curry at the weekend then reheat portions for dinner over the next 3 nights.

No problems 😊