Dear George,
Thank you for your response.
I had to update from 8.0 to 8.1, for example, because 8.0 is no longer a free version.
I was a bit hesitant to update all the plugins (even the ones I don’t actively use). But now after your advice I have updated everything and all pages work as they should. Glad you helped me with this.
I hope things continue to go well.