I can understand that it is frustrating for you if you are keen to get back to f2f. There are a ton of different reasons why someone wouldn't want to go back f2f under the circumstances, and some of them could well be beyond her comfort level with disclosure. She could have a health issue she is unwilling to disclose, or a close loved one might instead.
Whatever the reason, there is little you can do about it and that must feel disempowering. This whole pandemic situation is disempowering in so many ways!!