Canon Pixma Mg4250 does not recognize laptop?

I have the following problem: I have a wireless printer, Canon Pixma MG4250 and two laptops. I can print over Wi-Fi with one laptop, but not with the other. He sees the printer and sends the data, but the printer does not move - although it is online. And the print job disappears from the queue at some point, as if it had been done… Does anyone have any idea what the problem is here?

Did you connect the printer to the router as a network printer and also set it up as a network printer?

Router model?

Has it worked before and what have you changed?

Thank you for your questions - I checked it right away: I didn't have a network before - now I've activated it. I.e. 1. A PC - to which the laptop is connected with a cable, the PC also has a WLAN adapter and thus also sees the wireless output of the printer (which is called WS at the end). 2. A laptop that can print on the WS printer - but sometimes the message "Printer is not responding" appears even though it has already printed the document. This laptop also has a wireless adapter. 3. An Acer switch laptop, Windoes 10, with an integrated WLAN adapter. 4. The printer as a network printer, plus scanner.

Then I tried the following:

Printing from the PC to the WS device. Works quickly and flawlessly.
Printing from laptop 1 to WS: works in principle, only that he sees that the printer is not responding and the document remains on hold for a long time and the message comes that the printer is not responding, although the note has been out for a long time.
Attempt to print with Acer via WS: the printer switches on, and then - nothing. The document remains in the queue, at some point it is said that the printer is not responding. So so far similar to laptop 1. And at some point later it is out of the queue and the message is gone, but there's no slip of paper.
Printing with Acer via LAN cable, I thought, maybe Acer and printer don't speak the same language. But that worked perfectly.
Then I thought maybe the built-in wireless adapter is too weak and was using the external one from laptop 1. Exactly the same problem as before.
And now I can't think of anything else… Is there anything that the WLAN signal from Acer is converted into a language that the printer can't understand or something…

It's been a long time now, I'm sorry. But I have tried to describe it in as much detail as possible. Greetings Isabella

Oh yes: the router is Fritz-Box, I've had it new since yesterday, because I thought the problem was with that. But it didn't change you…

Uh, a lot of material… Unfortunately I'm not an expert on that either. I wrote with AVM (Fritzbox manufacturer) and received help.

I have to connect every device (every computer, laptop, mobile phone, tablet) directly to the Fritzbox. Regardless of whether WLAN 2.4 / 5 GHZ or LAN.

Then you have to install software for remote printers on every Windows device. The link was displayed to me when setting up the network printer in the Fritzbox in the FB on Screen Menu.

You install this software on each computer and then it works. So it was with me.

I'll try that, thank you for your help!