My Annuity (Pension) Moved From Fidelity NetBenefits to Athene Insurance. They Appear to Have Stolen My Money.

This past month (Dec 2025\], my longstanding company pension was moved by Charter Communications (formerly Time Warner Cable) from Fidelity to Athene Insurance. Per letters from Charter the amount of my pension would not change. I turned 65 in Nov 2025 but also moved to another state and didn't want to start any withdrawals until I left California. Well, after taking a last look at my statement on Fidelity's site which was very clear & concise btw, I registered with the Athene website and found almost a $1000 difference in a monthly payout & approximately a $150,000 difference in a lump sum payout. I called Fidelity after my initial call to Athene and they told me this makes no sense. I'm being run around in circles with Athene, their website is crap and they said they won't give me any definite amounts until I sign papers for an actual withdrawal of my annuity (pension\]. Can anyone here give me advice on what next steps to take? Should I hire a lawyer? If so what kind? Is there a state office I can go to about this? This company is in Des Moines Iowa but I live on the Tennessee/Kentucky border (Fort Campbell). TYIA for any suggestions.