I cannot recommend kiwi.com
I rarely write bad reviews, but here I need to advert you: the only purpose of that company ist to make money out of you. You pay every little thing very expensive, but you cannot get any customer service or quality out of it.
What went wrong: no refunds for cancelled flights, expensive administrative name change, the boarding card that you will need to print out yourself only arrives in the very last minute (soooo stressful when you travel with kids), not to be recommended. Bad company!