How to do string comparison on message received via sim900a gsm module in Arduino?

Iam currently doing a project in Arduino that does an action when I sent the string start as message. Iam not able to check whether the received string is start. I used serial.readString() to capture the message, but I can't perform string comparisons like endsWith. How can I compare whether the received... show more Iam currently doing a project in Arduino that does an action when I sent the string start as message. Iam not able to check whether the received string is start. I used serial.readString() to capture the message, but I can't perform string comparisons like endsWith. How can I compare whether the received message string has start in it,so that I can perform the action.
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