[Hummingbird Pro] Website's speed is very low

I am an existing Smush user for some time but decided to sign up today for the 7 day free trial with aim if converting this to the year’s Pro account.

I’m not sure why but I having the following issues now after activating the Pro trial.

1. Site loading speed is much slower per Google page speed insights:
– desktop was 80 now 35
– mobile was 58 now 9

2. I think because of the below mention error my website’s speed is very low.
Error : “Ensure text remains visible during webfont load” .

So could you please tell me how to resolve this error?
Waiting for your response.