Unlimited daily flat rate in the telecom network?

I need access to the Internet at different locations some days a year. (Not on the cell phone!)

I would like to connect several laptops to the Internet on site and need an unlimited flat rate for this day. Ideally in the telecom network, because I hope for the best and most stable coverage.

However, I only need this for a few non-contiguous days a year. An LTE router is available.

Does anyone know a tariff or provider with which I can implement this? Possibly. Prepaid so I can easily book it when I need it?

I'm familiar with Telekom's Dayflat Unlimited, but it does require an existing contract, which I do have, but I do not see changing my SIM from a smartphone to a router as a viable option.

Can you possibly give a hotspot for the router from your mobile phone? (I don't know if that's workable.)

You could connect the phone to the router and use the Magenta day flat. I myself used the unlimited flat from Magenta.

But I don't see plugging my SIM from my smartphone into the router as a viable option.

Do not understand where the problem is using your cell phone as a hot spot, but if just changing the plug is a problem, just get a second card.

Why don't you use the cell phone's hotspot function?

Just stumbled across your post here.

I just spontaneously think of using the whole thing via tethering, or just getting a MultiSIM for the contract.