Hi there and welcome
Can you tell me which model ZTE you have please?
You will have to do a factory reset of the phone. This will wipe all data from the phone and return it to new, but you cannot avoid this, it is the whole reason for the pattern lock.
To do the reset
Once done, the phone is as new and you can set it up and use it again
If you have any problems, or would like any additional information or assistance, please do not hesitate to let me know.
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