Constant no sim msg

[BarelyGood]

One ui 6, random no sim,  removed cleaned  never happened until update. 

Now constant no sim msg

[BruZZi]

Try Wiping Cache Partition:
https://techwiser.com/how-to-wipe-cache-partition-on-samsung-galaxy-phones-and-what-happens-when-you...

[BarelyGood]

I've done everything you can do. It just came back on a sec ago... until it decided to do it again

[3Fees]

Try this

https://www.samsung.com/ph/support/mobile-devices/how-to-fix-no-sim-card-detected-error-on-galaxy-ph...

Sim cards are generally free, you may want to get a new one.

Cheers
3Fees