I have 2 SIM cards in the Mi A2 (private / business). After work I deactivate the sim 2. Now it is so that the speakerphone in the car radio (Mercedes) after a change from LTE to H or E indicates no signal.
The A2 is normally connected to the radio but the reception indicator on the radio shows no reception and does not let me call.
However, if both sim cards are active it works.
Oneplus had the same problem with the 6er at the beginning (but was then fixed).
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