Hi @nickeva Yes , all the ports should be HDCP 2.2 compatible on the 2021 Frame and other Samsung Tv's from recent years. Firstly Input Signal Plus needs to be enabled for external Devices, turn this on via the External Device Manager Menu. This will be Settings-General-External Device Manager.
However if this is not the issue I would suggest you try a Factory Reset of the Tv initially and if still problem can you try a different port, just in case there is an issue with the other one. If that does not resolve it possibly there is a fault with the HDMI cable and just at that point it would be wise to try another cable if you have one or alternatively purchase. This need not cost too much,just ensure it is a high speed cable. https://www.techhive.com/article/3330376/do-i-need-a-4k-hdmi-cable.html