Considering the specs of the laptop and assuming the module is running at the max ram speed the CPU allows, you may not even need to buy another module if it's already running fast enough for your needs. If you were going to buy more ram, I would lean more toward suggesting 2x16GB if it's your main system and only if you also use it for productivity work that requires more than 16GB of ram. Otherwise, 2x8GB would be the best overall option to avoid incompatibility from mixing another module with your 16GB. In the future, when games may require more than 16GB, the GTX 1650 in the laptop would likely be too slow for the extra ram to matter.
If you really think you need more than 16GB, get either an 8GB or 16GB module to add in. If that doesn't work, return it for a refund or an exchange with a different single or dual module kit. This means you will need to make sure you can get at least a refund from where you are buying the module.
Personally I would just get an 8GB module to add to the original, because it should still work in hybrid mode with dual channel up to 16GB and I would be using my desktop system for production work that would require more than 16GB. If I had a problem with the new ram, I know I could usually diagnose any issues if it doesn't work as expected.
In CPU-Z, open the SPD tab to get the brand, part number and XMP settings of the module you have, so you can buy a matching module or something close. Also, check the memory tab for the current speed and timing of the module you have to see if XMP is enabled or if the DRAM frequency is 2933MT/s (1466MHz).