@Austroplebeia: Can you try going to Settings > Connections > Wi-Fi > Tap the 3 dots in the top right > Advanced > Turn On Wi-Fi Automatically > On, to see if this resolves your issue. If not, check your Wi-Fi Control History for any apps that have recently disabled your Wi-Fi. if you see any, head to Settings > Apps > Select the relevant app > Permissions, and disable any Wi-Fi related permissions from here.
Thanks for the advice however I've done everything there is possible to resolve the issue except factory reset which I suspect will not resolve the problem. My wife TabS 5e has the same issue since installing Android10. I have received a further update however this hasn't changed anything.