Need some suggestions on what to do with a cow

[DB]

I have been trying to get this one cow that I have breed for a month and a half now with no luck. She is in good body condition. She is getting up there in age but I would like to get a least one more calf from here. She is 10 yrs old I believe but in good body condition.  The first time we breed her we thought we had her and then she came back in heat so that time we breed her in the morning and evening. Still nothing she came in this morning and I noticed she was still in standing heat this evening yet so I am going to try one more time and breed again in morning and evening.  Any suggestions on trying something different.  I use the am/pm rule when breeding.  I don't think she is cystic because she is coming in regular. My ai guy normally picks up on a cow that is cystic.
Would like to get at least 1 more calf out of her.  10 is not to old is it?
thanks in advance.

 

[Simbeef10]

If she is having strong heats, are you sure the semen is good?  10 is not too old.  My oldest cow will be 12 next month and still is sound with a good udder, so needless to say, she will be bred again this year to calve again at 13