Fatal error: allowed memory exhausted

Hi,

I’m experiencing this trouble with the SpeakUp petitions plugin. My petition has more than 13,000 signatures, and when I try to export them as a CSV file this error shows up:

Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 72 bytes) in /home/respetamife2016/public_html/wp-content/plugins/speakout/includes/csv.php on line 28

I’ve read many posts in different sites in order to solve it (changing lines in wp-config.php, default-constants.php, etc.) but none of these ideas has solved the problem.

Actually, when I try to change the wp_memory_limit from 40M to 64M in default-constants.php this is the error I get:

Parse error: syntax error, unexpected ” );’ (T_CONSTANT_ENCAPSED_STRING) in /home/respetamife2016/public_html/wp-includes/default-constants.php on line 41

I think that my WordPress memory is 64M (I ran the test that this site suggests at the end) and the result is:

64M128M64M

(You can see it here: https://www.respetamife.es/prueba.php).

Does anyone have any ideas on how to solve this problem?

Thank you!