It looks like you forgot to send a message. Or else you used some taboo words blocked by the Chinese government.
There are too many different ways to phrase this text, the following is just one of them
Cantonese: 睇來妳唔記得發一個訊息。 或者妳用咗一啲避忌嘅字句，所以被中國政府刪咗？
Basically, the only serious grammar mistake is using '的' instead of '了' for final particle.
'了' indicates 'complete action' , '阻擋了' (blocked) indicates the action of 'blocking' is completed.
'了' indicates 'change of situation' '阻擋了' (blocked) indicates your message's status changed from 'being allowed' to 'being blocked'
'的' as a final particle add affirmative tone at the end, Since you started the sentence with "Or else", '中國政府阻擋的' is out of place here because "Or else" implies it is just your guess. If the sentence was "用了避忌的說話, 中國政府(是會)阻擋(的)" then it would have no problem.
The other mistakes are mostly poor choice of word. For example, 避忌的(字句) is much better than 避忌的(說話) when it comes to 'texting'. But it doesn't mean using 避忌的(說話) is grammatically incorrect .