First check whether removing dust from inside the connector helps.
If you do need to repair: the USB port is part of the mainboard. This part is currently not available and is not likely to become available, although Fairphone support has mentioned to contact support if you do need a part. Some repair shops have been able to re-solder the connector, or solder in a new one. If you need more information, please check the topic below and continue there if you have any questions:
Note that there are also external battery chargers, if you only need a temporary solution for access to the phone.