I2C SD2405 RTC Module time jumps

Hello
I am using an I2C SD2405 RTC Module for a data logging project. It ran ok for 8 hours the previous day then I noticed today that the clock has jumped by just over 5 hours (copied below).
The arduino was defiantly on with power to the clock at the time of the jump. The unit had been turned on two hours earlier after being off overnight and pulled the correct time.

The clock is mounted on a bread board shield on an arduino uno and was setup using the auto setup function from the library. The enclosure is mounted on the outside of a heated tunnel and is monitoring the temperatures in the tunnel. it is operating in a warm area however not near the +85°C. max operating temp. Could be reaching 40-45°C could this cause this effect?

Thanks in advance

2/8/2019 7:52 Sensor 1 : 88.75`C
Sensor 2 : 90.37`C
Sensor 3 : 85.44`C
2/8/2019 7:52 Sensor 1 : 88.75`C
Sensor 2 : 90.44`C
Sensor 3 : 85.50`C
2/8/2019 13:1 Sensor 1 : 88.81`C
Sensor 2 : 90.44`C
Sensor 3 : 85.00`C
2/8/2019 13:1 Sensor 1 : 88.75`C