Have you solved the problem?
I ask because I have a similar one. Admittedly concerning not an ESP, but an Arduino Mega 2560, but maybe some conclusions can be drawn.
I have a sizable project ready to go based on the Mega 2560, with a dozen or so different sensors, including 2 DHT11s, both connected on several metres of shielded twisted-pair cables. For a couple of months everything was humming along, until it suddenly stopped. - For no discernible reason

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Both sensors, instead of actual temperatures, show 0 (zero), reporting no errors . I have replaced the sensors. The ones removed, plugged directly into the PCB work just fine. The wires have been "rewired", everything seems to be o.k. (When everything was working, the sensors were read every 15 sec. Now that it's kicked in, I've changed this and am trying to read them at a higher rate as well: alternately, every 30 sec each - to no avail.
Do you have any ideas, as I've been sitting on this for a week now and "my hands have fallen off".
Greetings
P.S. I forgot an important one (perhaps for you):
When I was running my project, I also encountered checksum errors.
These were because the newer DHT11s labelled ASAIR (capacitive), require different libraries than the initial ones for the DHT11 AOSONG (resistive), and I started my attempts on the AOSONGs.