As a Swede in London, it's annoying that IKEA staff don't understand you when you pronounce the names correctly. You have to change letters (e.g. å is not a with an accent. It's a different letter) and read it like you don't know the language.
I'd suggest you look at it as funny and not annoying: IKEA in London, being a very multicultural place, likely has many non-native English speakers as well! When all else fails, you can always go back to the basic international language of gesturing, pointing and acting out the use of something to get to your point. (Or more boringly, point at the name on your phone) You could also try adapting pronounciation to what…
As a related anecdote, I found it surprising when I moved to Switzerland decades ago, that speaking high German wouldn't really work with foreign-looking shop assistants - they'd only speak and even understand Swiss German.