Called by apple that suspicious activity on iPhone

Apple does not make such calls.

All such calls are scams from criminals attempting to steal your personal and financial information. The callers will often use number spoofing to pretend they are calling from a legitimate business. The correct course of action is to ignore the calls or hang up on them, repeatedly if needed. 

Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams - Apple Support

You weren't called by apple you were called by scammers.

Hopefully you didn't give them any information. If you did, then consider it compromised. If passwords, change them. If banking details, call your bank and get cards etc. cancelled.

Your account isn't being hacked, you are.

They were probably calling numbers at random, and happened to get someone who uses in iPhone (not that hard to do). Or they had data about you from breaches of other organisations that suggested you have an iphone.

Either way, they were trying to trick you into handing over data. Hopefully you didn't, but if you did, then see my previous post. (shown just below this one)

emiledog wrote:

Do not know if my account is compromised

Please read replies above.