Chosen Solution
In the past few days my router, a Huawei B529s-23a from Austrian T-Online/Magenta, has been repeatedly dropping its connection to the Internet (wireless via LTE). The mode lamp which is normally blue goes red. I had the impression that the top of the router was warm - I don’t know whether that is the normal state or not. After power down and letting the router stand powered off for a while (15 mins or an hour) it then will work again for a while until again failing (e.g. after 15 mins - currently after about an hour powered off it is running somewhat longer). Any advice gratefully accepted!
I would contact your ISP if they supplied the Router as yours has failed, likely got a surge. If you own the Router you’ll need to get a new one. I do recommend you get a good surge suppressor and make sure the outlet you are using is properly wired. In some areas of Australia the power voltage maybe too high for your Router (as well as your PC and its peripherals). You should look at getting a voltage regulator or UPS to prevent your gear from being damaged.