Fatal error message when woocommerce plugin activated

When I activate my woocommerce plug in I get the error message below:

Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 196608 bytes) in /home/colleen24/public_html/wp-content/plugins/backwpup/inc/class-jobtype-wpexp.php on line 386

Which affects my site i.e I cannot access my media to add photos or add feature images. Why is this happening and what can I do about it?

https://wordpress.org/plugins/woocommerce/