According to the screenshot you sent me it shows 5g & 2g so you are okay. I don't have 2 sims...you also have the configuration set automatically so all should be fine. Is your phone working?
It means with the 5g & permitting 2g & the automatic settings in the advanced section on. Your phone should be okay now. VoLTE is actually voice over lte T-Mobile put you on 5g. You shouldn't have any problems. I have ultra but was actually using lte (4g) until last week when T-Mobile told me to toggle on my 5g. I had never seen using it but now I am.
