I could not receive or send image from Pixel 3 by message. Do you have the same issue?

Definitely follow the steps as per Fizz's FAQ

https://fizz.ca/en/faq/what-are-fizz-network-settings-apn

 

Also this seemed to help in my case. Edit manually both APN settings to change "APN protocol" and "APN roaming protocol" to "IPv4/IPv6"

Data has to be turned ON to send or receive MMS.

If the APN did not solved the problem, contact the support

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Verify that the APN settings are typed correctly and you didn't accidentally replace a dot with a comma etc. Then reboot your phone and test again, it's very likely an issue with the APN settings
Fizz APN settings are:
APN: mobile.bm
MMSC: http://mms.mobile.bm
MMS proxy: mmsproxy.mobile.bm
MMS port: 80
APN type: default,mms,supl