Samsung Galaxy A42 5g

All of a sudden, I am not able to receive text from my son on both my Smart and Globe SIMs. He gets all my messages but when he sends me a msg, it shows Sent on his end but I dont receive them.

I have no problem calling him or receiving his calls. There is no problem with texting between me and other contacts. He has no problem with his other contacts either.

He is not blocked on my phone. I am not blocked in his.

I only use Samsung Messages and Contacts apps. I've deleted my son from Contacts. I've also deleted all past conversations with him from Messages. I've cleared the cache on both apps. I've forced stop both apps, re-launched the apps and when that didnt work, I  restarted my phone. When that still didnt work, I turned my phone off, waited 5 mins and turned it back on. 

I called Samsung and they told me to reset my network settings. I did.

None of these worked. Any fresh ideas?