Grammarly have been very attentive and I received this email from them today:
Thanks for getting back to me.
Please rest assured that our technical team is already aware of the problem you reported, but unfortunately, we don’t currently have a solution to it. We know it's taking a long time to resolve — it turns out there are some technical considerations that our engineers need time to work through. We appreciate your patience and apologize for any inconvenience.
I'm in regular touch so hopefully it will be resolved soon