Solved - my bad. Used the wrong input.
MacBook Pro (16-inch, 2019)MacOS Monterey / Version: 12.4 (21F79)Graphics:  AMD Radeon Pro 5500M 4 GB / Intel UHD Graphics 630 1536 MB   I downloaded "Dell Display Manager Application for Mac OS"  and trying set up via USB Type-C Cable that came with U2720Q DELL Monitor and my MackBook can not to connect to DELL Monitor at all.On U2720Q DELL  - I see only message:"No USB Type-C Cable""The display will go into Standby mode in 4 minuts"On MacBook Pro (16-inch, 2019):"Please connect a supposted DELL monitor" 
U2720Q, MacBook Pro, Dell Display Manager Error