How to make my flash work in manual mode on EOS Rebel T7

[everett4]

Hi I recently got this camera (canon rebel t7) and it came with a flash in the kit set to connect to the camera but it's not working with it. When I press the test option on the external flash it works but when I go into flash control on the camera it says, "Menu not available. Flash is off or unsupported, or an accessory is attached". Also when I change from manual to any other mode the flash works fine just not in manual it seems. Please help

[rs-eos]

What specific flash do you have (make, model)?

[Tintype_18]

Question: Do you have the T7 manual downloaded on a tablet or laptop?