Verification Codes

I’ve just changed to a new carrier, everything is Woking fine but not when it comes to getting verification codes. For example, when I signed up for BeReal, I had to use my number. However the SMS regarding the Verification codes never came or came late by like 15-30 mins. I tried it again the next morning but it came instantly, I’m more confused.

Furthermore, when I tried to sign up for Snapchat using my number, I couldn’t receive any verification codes.

what do I do?