Peanut and shellfish allergy — how do I say it clearly in Sinhala or Tamil at a beach cafe?

Use a short card in English plus Sinhala and Tamil if you can, and say the key words out loud while showing it: allergy, no peanut, no prawn/shrimp/crab. Simple dishes help — plain rice, grilled fish you chose, fruit — and ask staff to confirm with the kitchen, not only the waiter. Phone translation screens work when the font is large and you point. I am not prescribing treatment; I am saying clear repetition beats hoping the menu is safe. If a place cannot understand or seems casual about it, eat elsewhere. Learn please and thank you; kindness helps attention.