Wrong hashrate for miner from API after running for a while

### Description

After running for a while, the API seems to increase the hashrate for individual miners until it changes to Infinity.

### Steps to Reproduce

1. Connect miner
2. Wait ~12hours
3. Hashrate changes to Infinity from the API

### Expected behavior

To reflect actual hashrate of the miner

### Actual behavior

Initially the hashrate is correct that's returned from the API.  After some time (several hours), it starts to increase.  Last I saw, it was approx 3X-4X of what it should be and then it just went to Infinity.  I've tested this on different coins and different algos.  I currently have X16r and X16s coins setup and it happens on both of those.

API endpoint: http://api.minerscore.com

### Reproduces how often

Everytime for the last couple days.

### Version

V26
Docker container running on CentOS 7.5

### Additional Information

The hashrate recorded in the database in minerstats is correct, it's just when returned form the API it changes.