Tyre pressure monitor driving me mad

[maxmw]

I just bought an approved used 2018 UK Polo SE two weeks ago.
On the way home from the dealership the tyre pressure warning light came on saying the front right tyre pressure had dropped. I pulled into a petrol station and checked all the pressures and noticed the front right was 2psi higher than the other tyres. I understand the tyre monitoring system uses the abs to determine if one tyre feels different to the rest and throws the warning. So I let some air out of the tyre so that the pressure was the same across all four tyres, reset the warning and continued to drive home.
Just before I got home the warning triggered again, I checked the tyre pressures again and all were the same, so I reset the system again. The system then went on to thrown the warning fives times over the course of the week! Each time I check pressures and reset, its driving me mad.

Last week I took the car back to VW to get check over, they checked for leaks and did a "hard reset" on the TPMS, they said they couldn't find anything wrong and that no error codes had been thrown. Since then the warning has triggered again three times, again each time the pressures are fine. So I have booked the car in with them tomorrow again.

Most of the time the warning doesn't specify which wheel is causing the problem.

Has anyone had a similar expericence with a 2018 onward polo? Or anyone have any ideas? Its getting very frustrating...

Thanks in advance!

[UMEL]

One of the tyre valve senders might be faulty. Has it had new tyres fitted and did the fitter leave the old senders or replace them.

My Passat still has its original sender valves even though its had new tyres fitted.