Can’t receive some calls since switch

[Drkat]

I switched to EE from Vodafone in oct 22. Since then a few people can’t call or text me. Call gets this persons phone is unavailable. Bank can’t text me to do 2 factor authentication. Most people it’s fine . Still happens when I move sim to another phone. I think something didn’t go right when my number was transfered. 
What can I do?

[Chris_B]

@Drkat  You need to call customer services and request your line be refreshed/reset. 

[Drkat]

Thanks. Yes spent some time talking to them. Their answer is to send me a new sim!
Despite a reset I’m still not getting calls from a couple of people.