You have a few choices here!
As you will have GEN1 TPMS, you could dig the battery out of the sensor, and change the battery, There's varying degrees of success here (there's a few vids on YouTube).
You could buy a GEN1 sensor, from a dealer or from another route. BMW Part number 36319832032 (approx £108 last time I looked)
Or "upgrade" to a new Gen2 sensor, BMW part number 36318567683
Better still, buy a Gen2 from Autodoc
https://moto.autodoc.co.uk/schrader/18314484 (about £44)
The Schrader 3141M is the same as the BMW item but without the BMW box, and a fraction of the price

Gen1 and Gen2 use the same frequency so are interchangeable.
If you have a GSA (wire wheels) you're best to buy a new valve at the same time (with spoke wheels the TPMS sensor is held in place by the valve stem, on alloy wheels it's a separate bolt)
For info these are the pics I took, and some of the data
View attachment 286888
Personally I would buy the 3141M from Autodoc - probably quickest and easiest - that's what I have done.