Timeout exception on Azure App Service

We suddenly started experiencing timeouts in production.

Stack:

• Azure App Service - P2v3

• Azure Redis Cache - P1 (tried with Redis on VM, same result)

• .NET (asp.net) - 6.0.28

• Microsoft.Extensions.Caching.StackExchangeRedis - 6.0.28

• CPU load like - 2% without spikes

• Network like - 30/40 connections/sec without spikes also

• There are no slow queries logged

Explored all options, read many articles.

• Upgrading from 2.2.4 to 2.8.0 made situation better but problem is not gone :(
• Tried increasing timeout from 5sec to 15sec didn't help

Timeout awaiting response (outbound=0KiB, inbound=0KiB, 15249ms elapsed, timeout is 15000ms), 
command=HMGET, next: HMGET PROD:Tenant:XXXXXXXXX, 
inst: 0, qu: 0, qs: 0, aw: False, 
bw: SpinningDown, rs: ReadAsync, ws: Idle, in: 0, last-in: 0, cur-in: 0, sync-ops: 42, async-ops: 117823, 
serverEndpoint: xxxxxxx.redis.cache.windows.net:6380, 
conn-sec: 2107.98, aoc: 0, mc: 1/1/0, mgr: 10 of 10 available, 
clientName: xxxxxxxxxx_c3f6697074(SE.Redis-v2.8.0.27420), 
IOCP: (Busy=0,Free=1000,Min=4,Max=1000), 
WORKER: (Busy=1,Free=32766,Min=4,Max=32767), 
POOL: (Threads=8,QueuedItems=0,CompletedItems=2910368,Timers=27), 
v: 2.8.0.27420 
(Please take a look at this article for some common client-side issues that can cause timeouts: https://stackexchange.github.io/StackExchange.Redis/Timeouts)

It would be great to have at least direction how to troubleshoot because now obvious reason for that

Start with the reported timeout trace and the linked StackExchange.Redis timeouts article, then compare the Azure App Service and Azure Redis Cache setup with the Redis-on-VM result. A useful outcome would be a reproducible cause or narrowed diagnosis for the HMGET timeouts, along with the configuration or workload conditions that trigger them.