The Cosmos Vega upgrade went live on block 8,695,000, which was at 22:57, Dec.14th, 2021(SGT). So features such as ATOM transfer and staking are not available for users of imToken 2.9.9 and below.
How to fix this?
Please upgrade to the latest version of imToken and then you can use the ATOM transfer and other functions as usual.
To update, simply update via Google Play or Apple App Store