Motorola Headset at Fritz hair dryer hand attachment usable?

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I possess a Motorola Headset (model designation is not unfortunately anywhere drauf) with 2.5 mm Stereoklinkenstecker.

If one sticks on it at the hand attachment Fritz hair dryer 7150, it remains dead.

Does this mean that it is defective (hab's given gotten with the info. it functions) or is it not compatibly?

If it is incompatible: Would it be possible to change this by “Umlten” of the contacts?

Or can recommend their to me alternatively a compatible Headset (which is available with realm ELT electronics perhaps even, there I there eh which order must)?

Thanks.

My old Headset “Siemens Gigaset 2000H”, to which I had soldered a 2,5mm jack plug before longer time (allocation here from the forum , grumbling ELT unfortunately. There are constantly misfires.
I cannot say whether there is contact problems at the plug or whether it concerns a defect directly in the Headset.