The message your Garmin gives you when it's full says it must be a Garmin branded SD card. I received this Garmin branded card in the mail and it is a typical SanDisk card. I could get a larger 8GB card for less if I bought the Sandisk branding. Garmin wasn't impressed.
Kingston microSDXC 64GB Class 10, V10, A1, UHS-I U1, R 100MB/s Memory Card, SD Adapter, 1 pc, Black
45 Review
32GB High-Speed Micro SDHC Card - Class 10 UHS-I Compatible Memory Card for SD Devices
63 Review
Smartphone Xiaomi Mi 8 Lite 6/128 GB, midnight black
70 Review
Silicon Power Elite 64GB microSDXC 2-Pack Memory Card with Adapter for Nintendo Switch and Wyze Cam
57 Review